CVE-2018-19518

CRITICALNVD 7.59.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because EPSS predicted 96% probability of exploitation within the next 30 days (99th percentile of EPSS-scored CVEs) when EchelonGraph scored this CVE. NVD baseline CVSS 7.5 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction (continuous uplift above 30%)
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this weekWeaponized

Also known asEUVD-2018-11207 (ENISA EUVD) · GHSA-5qmr-54g6-4256 (GitHub Security Advisories)Source: ENISA EUVD

9.0EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High exploitation likelihood — EPSS 96%
  • Public exploit code is available (Metasploit, Exploit-DB, marked verified by Exploit-DB, other public proof-of-concept code)
CISA-KEV: Not listedEPSS PROB: 96%CVSS: 7.5Exploit: Metasploit · Exploit-DB (verified) · other public PoCExposed services: Not assessed

A fix is available — apply it.

University of Washington IMAP Toolkit 2007f on UNIX, as used in imap_open() in PHP and other products, launches an rsh command (by means of the imap_rimap function in c-client/imap4r1.c and the tcp_aopen function in osdep/unix/tcp_unix.c) without preventing argument injection, which might allow remote attackers to execute arbitrary OS commands if the IMAP server name is untrusted input (e.g., entered by a user of a web application) and if rsh has been replaced by a program with different argument semantics. For example, if rsh is a link to ssh (as seen on Debian and Ubuntu systems), then the attack can use an IMAP server name containing a "-oProxyCommand" argument.

CVSS v3
7.5
EG Score
9.0CRITICALhigh confidence
EG Risk
72
EG Risk 72/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation96% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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 at low or medium mission impact and sooner than that at high.
EPSS PROB
96%
EPSS %ILE
99th
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 (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is EPSS's lift toward 9.0 from its impact severity (EG Severity, CVSS 7.5 HIGH): a likelihood of exploitation, not impact.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
96% 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 low, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 14 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 low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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)14 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's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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

November 25, 2018

Last Modified

November 21, 2024

Advisory Details (7)

Auto-updated Oct 14, 2026
Patch available.
Web page

PHP :: Sec Bug #77160 :: Script injection in imap_open()

https://bugs.php.net/bug.php?id=77160
Web page

PHP :: Sec Bug #77153 :: imap_open allows to run arbitrary shell commands via mailbox parameter

https://bugs.php.net/bug.php?id=77153
Web page

PHP :: Sec Bug #76428 :: Command execution through imap_open

https://bugs.php.net/bug.php?id=76428
Web pageMentions a patch (unverified)

#913836 - php7.0-imap: CVE-2018-19518: imap_open() function command injection - Debian Bug report logs

https://bugs.debian.org/913836
Web page

#913835 - php7.2-imap: CVE-2018-19518: imap_open() function command injection - Debian Bug report logs

https://bugs.debian.org/913835
Web pageMentions a patch (unverified)

#913775 - php7.3-imap: CVE-2018-19518: imap_open() function command injection - Debian Bug report logs

https://bugs.debian.org/913775
Web page

CVE-2018-19518 - PSIRT.COM

http://www.securityfocus.com/bid/106018

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntuuw-mailutils (8:2007f~dfsg-4+deb8u1build0.16.04.1) @ xenial2026-11-02ubuntu

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

(6 across 4 ecosystems)
Debian:8(2)
PackageVulnerable rangeFix by version rangeDependents
php55.6.11+dfsg-1 ... 5.6.9+dfsg-1 (44 versions)
  • every version up to 5.6.39+dfsg-0+deb8u1: fixed in 5.6.39+dfsg-0+deb8u1
—
uw-imap8:2007f~dfsg-4
  • every version up to 8:2007f~dfsg-4+deb8u1: fixed in 8:2007f~dfsg-4+deb8u1
—
Debian:9(2)
PackageVulnerable rangeFix by version rangeDependents
php7.07.0.19-1 ... 7.0.32-1 (17 versions)
  • every version up to 7.0.33-0+deb9u1: fixed in 7.0.33-0+deb9u1
—
uw-imap8:2007f~dfsg-5
  • every version up to 8:2007f~dfsg-5+deb9u1: fixed in 8:2007f~dfsg-5+deb9u1
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
uw-imap—
  • every version up to 8:2007f~dfsg-6: fixed in 8:2007f~dfsg-6
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
uw-imap—
  • every version up to 8:2007f~dfsg-6: fixed in 8:2007f~dfsg-6
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 23× in last 7d / 63× 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 93 of 111 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. 7 repeat rows among the latest 100 are merged into the row they repeat. The 18 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-02 09:17 UTCEG score recompute
  2. 2026-11-02 09:17 UTCVendor advisory
  3. 2026-11-02 09:17 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  4. 2026-11-01 10:53 UTCEG score recompute
  5. 2026-11-01 10:53 UTCVendor advisory
  6. 2026-11-01 10:53 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  7. 2026-10-31 12:29 UTCEG score recompute
  8. 2026-10-31 12:29 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  9. 2026-10-30 14:06 UTCEG score recompute
  10. 2026-10-30 14:06 UTCVendor advisory
  11. 2026-10-30 14:06 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  12. 2026-10-29 15:42 UTCVendor advisory
  13. 2026-10-29 15:42 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  14. 2026-10-28 17:08 UTCEG score recompute
  15. 2026-10-28 17:08 UTCVendor advisory
  16. 2026-10-28 17:08 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  17. 2026-10-28 16:27 UTCEPSS rescoreEPSS 96% · 99th percentile
  18. 2026-10-27 18:44 UTCEG score recompute
  19. 2026-10-27 18:44 UTCVendor advisory
  20. 2026-10-27 18:44 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  21. 2026-10-26 20:20 UTCEG score recompute
  22. 2026-10-26 20:20 UTCVendor advisory
  23. 2026-10-26 20:20 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  24. 2026-10-25 20:08 UTCVendor advisory
  25. 2026-10-25 20:08 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
Show 68 more
  1. 2026-10-25 19:20 UTCEG score recompute
  2. 2026-10-25 16:27 UTCEPSS rescoreEPSS 96% · 99th percentile
  3. 2026-10-24 21:44 UTCEG score recompute
  4. 2026-10-24 21:44 UTCVendor advisory
  5. 2026-10-24 21:44 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  6. 2026-10-23 23:21 UTCEG score recompute
  7. 2026-10-23 23:21 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  8. 2026-10-23 00:52 UTCEG score recompute
  9. 2026-10-23 00:52 UTCVendor advisory
  10. 2026-10-23 00:52 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  11. 2026-10-22 02:07 UTCEG score recompute
  12. 2026-10-22 02:06 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  13. 2026-10-21 16:27 UTCEPSS rescoreEPSS 96% · 99th percentile
  14. 2026-10-21 03:38 UTCEG score recompute
  15. 2026-10-21 03:38 UTCVendor advisory
  16. 2026-10-21 03:38 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  17. 2026-10-20 05:11 UTCEG score recompute
  18. 2026-10-20 05:11 UTCVendor advisory
  19. 2026-10-20 05:11 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  20. 2026-10-19 06:21 UTCEG score recompute
  21. 2026-10-19 06:21 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  22. 2026-10-18 07:57 UTCEG score recompute
  23. 2026-10-18 07:56 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  24. 2026-10-17 09:29 UTCEG score recompute
  25. 2026-10-17 09:28 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  26. 2026-10-16 16:30 UTCEPSS rescoreEPSS 96% · 99th percentile
  27. 2026-10-16 11:03 UTCEG score recompute
  28. 2026-10-16 11:02 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  29. 2026-10-15 16:27 UTCEPSS rescoreEPSS 96% · 99th percentile
  30. 2026-10-15 11:12 UTCEG score recompute
  31. 2026-10-15 11:12 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  32. 2026-10-14 16:27 UTCEPSS rescoreEPSS 96% · 99th percentile
  33. 2026-10-14 06:56 UTCEG score recompute
  34. 2026-10-14 06:56 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  35. 2026-10-13 02:14 UTCGHSA enrichmentGHSA-5qmr-54g6-4256 · GitHub severity HIGH · GitHub CVSS 7.5
  36. 2026-10-12 20:13 UTCEG score recompute
  37. 2026-10-12 00:37 UTCEG score recompute
  38. 2026-10-07 23:42 UTCEPSS rescoreEPSS 96% · 99th percentile
  39. 2026-09-30 14:59 UTCEPSS rescoreEPSS 96% · 99th percentile
  40. 2026-09-30 09:58 UTCEG score recompute
  41. 2026-09-28 16:42 UTCOSV refresh
  42. 2026-09-24 13:59 UTCEPSS rescoreEPSS 96% · 99th percentile
  43. 2026-09-19 15:36 UTCEPSS rescoreEPSS 95% · 99th percentile
  44. 2026-09-16 05:06 UTCEPSS rescoreEPSS 95% · 99th percentile
  45. 2026-09-08 21:34 UTCOSV refresh
  46. 2026-09-06 13:43 UTCEPSS rescoreEPSS 95% · 99th percentile
  47. 2026-09-05 15:24 UTCEPSS rescoreEPSS 95% · 99th percentile
  48. 2026-08-28 21:36 UTCEPSS rescoreEPSS 95% · 99th percentile
  49. 2026-08-26 14:42 UTCEPSS rescoreEPSS 95% · 99th percentile
  50. 2026-08-25 13:44 UTCEPSS rescoreEPSS 95% · 99th percentile
  51. 2026-08-22 06:37 UTCOSV refresh
  52. 2026-08-16 02:10 UTCEPSS rescoreEPSS 95% · 99th percentile
  53. 2026-08-12 13:46 UTCEPSS rescoreEPSS 95% · 99th percentile
  54. 2026-08-06 09:40 UTCOSV refresh
  55. 2026-07-26 14:51 UTCEPSS rescoreEPSS 95% · 99th percentile
  56. 2026-07-23 01:35 UTCEG score recompute
  57. 2026-07-22 22:15 UTCEG score recompute
  58. 2026-07-21 02:47 UTCOSV refresh
  59. 2026-07-07 13:42 UTCEPSS rescoreEPSS 95% · 99th percentile
  60. 2026-07-05 02:27 UTCEPSS rescoreEPSS 95% · 99th percentile
  61. 2026-07-03 21:56 UTCOSV refresh
  62. 2026-06-24 14:02 UTCEPSS rescoreEPSS 95% · 99th percentile
  63. 2026-06-23 21:30 UTCEPSS rescoreEPSS 95% · 99th percentile
  64. 2026-06-18 17:50 UTCEPSS rescoreEPSS 95% · 99th percentile
  65. 2026-06-15 17:45 UTCEPSS rescoreEPSS 95% · 99th percentile
  66. 2026-06-15 09:43 UTCOSV refresh
  67. 2026-06-11 13:57 UTCEPSS rescoreEPSS 94% · 99th percentile
  68. 2026-06-10 13:19 UTCEPSS rescoreEPSS 94% · 99th percentile

Publicly available exploits

(3 references)

Public exploit code is referenced for this CVE (1 Metasploit module, 1 Exploit-DB entry, 1 GitHub PoC). Defenders should treat patch urgency accordingly.

  • Exploit-DBEDB-45914✓ verified
    Published Nov 29, 2018

    PHP imap_open - Remote Code Execution (Metasploit)

    Open source ↗
  • Metasploitexploit/linux/http/php_imap_open_rce✓ verified
    Published Nov 27, 2018

    php imap_open Remote Code Execution

    Open source ↗
  • GitHub PoChouqe/EXP_CVE-2018-19518
    Published Apr 15, 2023
    Open source ↗

Frequently asked(5)

What is CVE-2018-19518?
CVE-2018-19518 is a critical-severity vulnerability; its CVE record was published on November 25, 2018. University of Washington IMAP Toolkit 2007f on UNIX, as used in imap_open() in PHP and other products, launches an rsh command (by means of the imap_rimap function in c-client/imap4r1.c and the tcp_aopen function in osdep/unix/tcp_unix.c) without preventing argument injection, which might allow…
When was CVE-2018-19518 made public?
CVE-2018-19518 was made public on November 25, 2018: that is the date its CVE record's CNA, MITRE Corporation, gives for when the vulnerability was made public. The CVE record itself was published on November 25, 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-2018-19518 actively exploited?
CVE-2018-19518 is not currently on CISA's Known Exploited Vulnerabilities catalog. EchelonGraph's EG-KEV model places it in Tier 2 (Weaponized), which is not evidence of exploitation: a Metasploit module exists for it, and Exploit-DB marks a public exploit for it as verified. EchelonGraph does not test whether exploit code works. FIRST EPSS estimates a 96% probability of exploitation in the next 30 days (99th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2018-19518?
CVE-2018-19518 has a CVSS v3 base score of 7.5 (NVD). EchelonGraph synthesises NVD + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
How do I remediate CVE-2018-19518?
A fix for CVE-2018-19518 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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