Curl versions 7.33.0 through 7.61.1 are vulnerable to a buffer overrun in the SASL authentication code that may lead to denial of service.
CVE-2018-16839
CRITICALNVD 4.39.8Trending — 5 sources updated this week
EchelonGraph scoreMEDIUM confidence
“▲” beside the score: it is higher than NVD's CVSS score.
Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2022-05-13. NVD baseline CVSS 4.3; sources differ by 5.5.
Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Also known asEUVD-2018-8635 (ENISA EUVD) · GHSA-g54v-fj63-pm34 (GitHub Security Advisories)Source: ENISA EUVD
9.8EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 5.8%CVSS: 4.3Exploit: None knownExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 4.3
- EG Score
- 9.8CRITICALmedium confidence
- EG Risk
- 46EG Risk 46/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity98% × 45%Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation5.8% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 5.8%
- EPSS %ILE
- 93rd
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 5.8% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
October 31, 2018
Last Modified
November 21, 2024
Advisory Details (6)
Auto-updated Oct 14, 2026Patch available. Sources: github_commit, redhat.
Web page
cURL: Multiple vulnerabilities (GLSA 201903-03) — Gentoo security
https://security.gentoo.org/glsa/201903-03Web pageMentions a patch (unverified)
[SECURITY] [DLA 1568-1] curl security update
https://lists.debian.org/debian-lts-announce/2018/11/msg00005.htmlWeb page
Pony Mail
https://lists.apache.org/thread.html/8338a0f605bdbb3a6098bb76f666a95fc2b2f53f37fa1ecc89f1146f%40%3Cdevnull.infra.apache.org%3EGitHub commit
commit f3a24d7916b9 (curl/curl)
Fix landed in curl/curl commit f3a24d7916b9 — awaiting tagged release
https://github.com/curl/curl/commit/f3a24d7916b9173c69a3e0ee790102993833d6c5Web page
curl - SASL password overflow via integer overflow - CVE-2018-16839
https://curl.haxx.se/docs/CVE-2018-16839.htmlRed HatMentions a patch (unverified)
1642201 – (CVE-2018-16839) CVE-2018-16839 curl: Integer overflow leading to heap-based buffer overflow in Curl_sasl_create_plain_message()
Affected: Red Hat Enterprise Linux 7 and earlier, which are based on upstream Curl versions prior to 7.33.0.
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16839Vendor Advisories for CVE-2018-16839(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Patch Availability(2)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| ubuntu | libcurl4-openssl-dev (7.35.0-1ubuntu2.19) @ trusty | 2026-11-02 | ubuntu |
| redhat | patch | 2019-06-18 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(26 across 26 ecosystems)
Alpine:v3.10(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.11(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.15(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.16(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.17(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.18(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.19(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.20(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.21(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.22(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.23(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.24(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.5(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.6(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.7(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.8(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Alpine:v3.9(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Debian:11(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | — |
| — |
Debian:8(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | 7.38.0-4 ... 7.38.0-4+deb8u9 (13 versions) |
| — |
Debian:9(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| curl | 7.52.1-5 ... 7.52.1-5+deb9u7 (8 versions) |
| — |
Weakness Classification(3)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(1)
Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.
Data Freshness Timeline
(refreshed 28× in last 7d / 96× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 100 of 258 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 158 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-02 21:25 UTCOSV refresh
- 2026-11-02 16:34 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-11-02 08:07 UTCEG score recompute
- 2026-11-02 08:07 UTCVendor advisory
- 2026-11-02 08:07 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-11-01 16:28 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-11-01 09:49 UTCEG score recompute
- 2026-11-01 09:49 UTCVendor advisory
- 2026-11-01 09:49 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-31 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-31 11:31 UTCEG score recompute
- 2026-10-31 11:31 UTCVendor advisory
- 2026-10-31 11:31 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-30 16:28 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-30 13:14 UTCEG score recompute
- 2026-10-30 13:14 UTCVendor advisory
- 2026-10-30 13:14 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-29 16:28 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-29 14:56 UTCVendor advisory
- 2026-10-29 14:56 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-28 16:39 UTCEG score recompute
- 2026-10-28 16:39 UTCVendor advisory
- 2026-10-28 16:39 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-28 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-27 18:20 UTCEG score recompute
Show 75 moreShow fewer
- 2026-10-27 18:20 UTCVendor advisory
- 2026-10-27 18:20 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-27 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-26 20:02 UTCEG score recompute
- 2026-10-26 20:02 UTCVendor advisory
- 2026-10-26 20:02 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-26 16:26 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-25 19:45 UTCVendor advisory
- 2026-10-25 19:45 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-25 19:22 UTCEG score recompute
- 2026-10-25 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-24 21:28 UTCEG score recompute
- 2026-10-24 21:28 UTCVendor advisory
- 2026-10-24 21:28 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-24 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-23 23:10 UTCEG score recompute
- 2026-10-23 23:10 UTCVendor advisory
- 2026-10-23 23:10 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-23 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-23 00:30 UTCEG score recompute
- 2026-10-23 00:30 UTCVendor advisory
- 2026-10-23 00:29 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-22 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-22 01:45 UTCEG score recompute
- 2026-10-22 01:45 UTCVendor advisory
- 2026-10-22 01:44 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-21 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-21 03:25 UTCEG score recompute
- 2026-10-21 03:25 UTCVendor advisory
- 2026-10-21 03:24 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-20 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-20 05:05 UTCEG score recompute
- 2026-10-20 05:05 UTCVendor advisory
- 2026-10-20 05:05 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-19 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-19 06:10 UTCEG score recompute
- 2026-10-19 06:10 UTCVendor advisory
- 2026-10-19 06:10 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-18 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-18 07:48 UTCEG score recompute
- 2026-10-18 07:48 UTCVendor advisory
- 2026-10-18 07:47 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-17 16:27 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-17 09:29 UTCEG score recompute
- 2026-10-17 09:29 UTCVendor advisory
- 2026-10-17 09:29 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-16 16:30 UTCEPSS rescoreEPSS 5.8% · 93rd percentile
- 2026-10-16 11:10 UTCEG score recompute
- 2026-10-16 11:10 UTCVendor advisory
- 2026-10-16 11:10 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-15 16:27 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-15 11:22 UTCEG score recompute
- 2026-10-15 11:22 UTCVendor advisory
- 2026-10-15 11:21 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-14 16:27 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-14 07:04 UTCEG score recompute
- 2026-10-14 07:04 UTCVendor advisory
- 2026-10-14 07:04 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-13 16:27 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-13 02:21 UTCVendor advisory
- 2026-10-13 02:21 UTCGHSA enrichmentGHSA-g54v-fj63-pm34 · GitHub severity CRITICAL · GitHub CVSS 9.8
- 2026-10-12 20:15 UTCEG score recompute
- 2026-10-12 16:28 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-12 00:39 UTCEG score recompute
- 2026-10-11 13:41 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-10 19:55 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-09 20:02 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-08 16:36 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-07 23:41 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-06 15:12 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-05 17:39 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-10-03 14:21 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-09-30 14:59 UTCEPSS rescoreEPSS 5.8% · 92nd percentile
- 2026-09-30 09:55 UTCEG score recompute
- 2026-09-28 17:13 UTCOSV refresh
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownDebian:9:curl
- CVE-2018-14618NVD 7.5EG 9.8EPSS p96CRITICAL
- CVE-2018-1000120EG 9.8EPSS p96CRITICAL
- CVE-2017-8817EG 9.8EPSS p96CRITICAL
- CVE-2017-8816EG 9.8EPSS p95CRITICAL
- CVE-2018-16842NVD 4.4EG 9.1CRITICAL
- CVE-2018-1000301EG 9.1EPSS p93CRITICAL
- CVE-2018-1000122EG 9.1EPSS p95CRITICAL
- CVE-2017-1000257EG 9.1EPSS p94CRITICAL
- CVE-2018-1000121EG 7.5EPSS p95HIGH
- CVE-2017-1000101EG 6.5EPSS p90MEDIUM
Same vendor
10 shownredhat:RHSA-2019:1543
- CVE-2018-16840EG 9.8CRITICAL
- CVE-2018-16842NVD 4.4EG 9.1CRITICAL
- CVE-2019-3822EG 9.8EPSS p96CRITICAL
- CVE-2018-1000120EG 9.8EPSS p96CRITICAL
- CVE-2018-1000007EG 9.8EPSS p96CRITICAL
- CVE-2018-1000122EG 9.1EPSS p95CRITICAL
- CVE-2018-1000005EG 9.1EPSS p92CRITICAL
- CVE-2019-0211NVD 7.8EG 9.0 KEVEPSS p99CRITICAL
- CVE-2019-5436NVD 7.8EG 8.2EPSS p99HIGH
- CVE-2018-0732NVD 7.5EG 8.0EPSS p99HIGH
Same CWE
10 shownCWE-119 · CWE-122 · CWE-190
Frequently asked(5)
What is CVE-2018-16839?
CVE-2018-16839 is a critical-severity vulnerability; its CVE record was published on October 31, 2018. Curl versions 7.33.0 through 7.61.1 are vulnerable to a buffer overrun in the SASL authentication code that may lead to denial of service.
When was CVE-2018-16839 made public?
CVE-2018-16839 was made public on October 31, 2018: that is the date its CVE record's CNA, Red Hat, Inc., gives for when the vulnerability was made public. The CVE record itself was published on October 31, 2018. EchelonGraph's copy of the record carries a last-modified date of November 21, 2024; the record at its source may have been updated since.
Is CVE-2018-16839 actively exploited?
CVE-2018-16839 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 5.8% probability of exploitation in the next 30 days (93rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2018-16839?
CVE-2018-16839 has a CVSS v3 base score of 4.3 (NVD). EchelonGraph synthesises NVD + FIRST EPSS + GHSA into a combined EG score of 9.8 (CRITICAL).
How do I remediate CVE-2018-16839?
A fix for CVE-2018-16839 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2018-16839 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2018-16839
Is Your Infrastructure Affected by CVE-2018-16839?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.