An attacker may cause an HTTP/2 endpoint to read arbitrary amounts of header data by sending an excessive number of CONTINUATION frames. Maintaining HPACK state requires parsing and processing all HEADERS and CONTINUATION frames on a connection. When a request's headers exceed MaxHeaderBytes, no memory is allocated to store the excess headers, but they are still parsed. This permits an attacker to cause an HTTP/2 endpoint to read arbitrary amounts of header data, all associated with a request which is going to be rejected. These headers can include Huffman-encoded data which is significantly more expensive for the receiver to decode than for an attacker to send. The fix sets a limit on the amount of excess header frames we will process before closing a connection.
CVE-2023-45288
“▲” beside the score: it is higher than NVD's CVSS score.
Score elevated to 9.0 because EPSS predicted 92% 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.
Also known asEUVD-2024-1094 (ENISA EUVD) · GHSA-4v7x-pqxf-cx7m (GitHub Security Advisories)Source: ENISA EUVD
- High exploitation likelihood — EPSS 92%
- Public exploit or proof-of-concept code is available
A fix is available — apply it.
- CVSS v3
- 7.5
- EG Score
- 9.0CRITICALhigh confidence
- EG Risk
- 86EG Risk 86/100
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.Exploitation92% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability100% × 15%CISA's SSVC Automatable value: yes (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable yes (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 at low or medium mission impact and sooner than that at high. - EPSS PROB
- 92%
- 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.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 92% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). 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 or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days 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 or medium mission impact; Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (CISA Vulnrichment) · Automatable yes (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)14 days if the affected system is publicly exposed; 60 days if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (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
April 4, 2024
Last Modified
April 15, 2026
Advisory Details (8)
Auto-updated Oct 13, 2026oss-security - Go 1.22.2 and 1.21.9 (CVE-2023-45288 HTTP/2 CONTINUATION issue)
http://www.openwall.com/lists/oss-security/2024/04/05/4oss-security - CERT/CC VU#421644: HTTP/2 CONTINUATION frames can be utilized for DoS attacks
http://www.openwall.com/lists/oss-security/2024/04/03/16[SECURITY] Fedora 40 Update: kubernetes-1.29.4-1.fc40 - package-announce - Fedora mailing-lists
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QRYFHIQ6XRKRYBI2F5UESH67BJBQXUPT/net/http, x/net/http2: close connections when receiving too many headers (CVE-2023-45288) · Issue #65051 · golang/go · GitHub
https://go.dev/issue/65051Vendor Advisories for CVE-2023-45288(20)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:83627Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat OpenShift Data Foundation 4.14.40 security, enhancement & bug fix update
- RHSA-2025:15828Red Hat Product SecurityHigh
Red Hat Security Advisory: updated web-terminal/tooling container image
- RHSA-2025:8274Red Hat Product SecurityHigh
Red Hat Security Advisory: Errata Advisory for Red Hat OpenShift GitOps v1.14.4 security update
- RHSA-2025:7753Red Hat Product SecurityHigh
Red Hat Security Advisory: Errata Advisory for Red Hat OpenShift GitOps v1.15.2 security update
- RHSA-2025:4240Red Hat Product SecurityHigh
Red Hat Security Advisory: Updated 6.1 container image is now available in the Red Hat Ecosystem Catalog.
- RHSA-2024:6122Red Hat Product SecurityHigh
Red Hat Security Advisory: OpenShift Container Platform 4.18.1 bug fix and security update
- RHBA-2025:1772Red Hat Product SecurityHigh
Red Hat Bug Fix Advisory: Updated 7.1 container image is now available in the Red Hat Ecosystem Catalog
- RHSA-2025:0832Red Hat Product SecurityHigh
Red Hat Security Advisory: OpenShift Container Platform 4.12.72 bug fix and security update
- +12 more
Patch Availability(33)
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
(10 across 5 ecosystems)
Go(4)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| golang.org/x/net | — |
| — |
| golang.org/x/net/http2 | — |
| — |
| net/http | — |
| — |
| stdlib | — |
| — |
Debian:11(2)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| golang-1.15 | 1.15.15-1 ... 1.15.9-6 (10 versions) |
| — |
| golang-golang-x-net | 1:0.0+git20210119.5f4716e+dfsg-4 ... 1:0.7.0+dfsg-1 (40 versions) |
| — |
Debian:12(2)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| golang-1.19 | 1.19.10-1 ... 1.19.9-1 (12 versions) |
| — |
| golang-golang-x-net | 1:0.10.0-1 ... 1:0.7.0+dfsg-1 (27 versions) |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| golang-golang-x-net | — |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| golang-golang-x-net | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(24)
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.
- Microsoft MSRCCVE-2023-452882024-04-08
HTTP/2 CONTINUATION flood in net/http
- Red HatRHBA-2024:2646IMPORTANT2024-04-03
RHBA-2024:2646 — Important
- Red HatRHBA-2024:2647IMPORTANT2024-04-03
RHBA-2024:2647 — Important
- Red HatRHBA-2024:2648IMPORTANT2024-04-03
RHBA-2024:2648 — Important
- Red HatRHBA-2024:2649IMPORTANT2024-04-03
RHBA-2024:2649 — Important
- Red HatRHBA-2024:3470IMPORTANT2024-04-03
RHBA-2024:3470 — Important
- Red HatRHBA-2024:4181IMPORTANT2024-04-03
RHBA-2024:4181 — Important
- Red HatRHBA-2025:1479IMPORTANT2024-04-03
RHBA-2025:1479 — Important
- Red HatRHEA-2024:2635IMPORTANT2024-04-03
RHEA-2024:2635 — Important
- Red HatRHEA-2024:4022IMPORTANT2024-04-03
RHEA-2024:4022 — Important
- Red HatRHSA-2024:1616IMPORTANT2024-04-03
RHSA-2024:1616 — Important
- Red HatRHSA-2024:1668IMPORTANT2024-04-03
RHSA-2024:1668 — Important
- Red HatRHSA-2024:1679IMPORTANT2024-04-03
RHSA-2024:1679 — Important
- Red HatRHSA-2024:1681IMPORTANT2024-04-03
RHSA-2024:1681 — Important
- Red HatRHSA-2024:1683IMPORTANT2024-04-03
RHSA-2024:1683 — Important
- Red HatRHSA-2024:1892IMPORTANT2024-04-03
RHSA-2024:1892 — Important
- Red HatRHSA-2024:1897IMPORTANT2024-04-03
RHSA-2024:1897 — Important
- Red HatRHSA-2024:1899IMPORTANT2024-04-03
RHSA-2024:1899 — Important
- Red HatRHSA-2024:1962IMPORTANT2024-04-03
RHSA-2024:1962 — Important
- Red HatRHSA-2024:1963IMPORTANT2024-04-03
RHSA-2024:1963 — Important
- Red HatRHSA-2024:2049IMPORTANT2024-04-03
RHSA-2024:2049 — Important
- Red HatRHSA-2024:2060IMPORTANT2024-04-03
RHSA-2024:2060 — Important
- Red HatRHSA-2024:2062IMPORTANT2024-04-03
RHSA-2024:2062 — Important
- Red HatRHSA-2024:2068IMPORTANT2024-04-03
RHSA-2024:2068 — Important
Data Freshness Timeline
(refreshed 17× in last 7d / 52× 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 89 of 148 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. 11 repeat rows among the latest 100 are merged into the row they repeat. The 59 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-01 15:04 UTCVendor advisory
- 2026-11-01 15:04 UTCGHSA enrichmentGHSA-4v7x-pqxf-cx7m · GitHub severity MODERATE · GitHub CVSS 5.3
- 2026-11-01 08:18 UTCGHSA enrichmentGHSA-4v7x-pqxf-cx7m · GitHub severity MODERATE · GitHub CVSS 5.3
- 2026-11-01 08:18 UTCEG score recompute
- 2026-10-31 13:02 UTCEG score recompute
- 2026-10-31 13:02 UTCVendor advisory
- 2026-10-30 10:58 UTCEG score recompute
- 2026-10-30 10:58 UTCVendor advisory
- 2026-10-29 16:30 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-29 08:56 UTCEG score recompute
- 2026-10-29 08:56 UTCVendor advisory
- 2026-10-28 16:29 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-28 06:48 UTCEG score recompute
- 2026-10-28 06:48 UTCVendor advisory
- 2026-10-27 16:29 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-27 04:45 UTCEG score recompute
- 2026-10-27 04:45 UTCVendor advisory
- 2026-10-25 22:19 UTCVendor advisory
- 2026-10-25 17:33 UTCEG score recompute
- 2026-10-25 16:29 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-24 20:15 UTCEG score recompute
- 2026-10-24 20:15 UTCVendor advisory
- 2026-10-23 18:12 UTCEG score recompute
- 2026-10-23 18:12 UTCVendor advisory
- 2026-10-22 16:09 UTCEG score recompute
Show 64 moreShow fewer
- 2026-10-22 16:09 UTCVendor advisory
- 2026-10-21 16:29 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-21 13:32 UTCEG score recompute
- 2026-10-21 13:32 UTCVendor advisory
- 2026-10-20 16:30 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-20 11:30 UTCEG score recompute
- 2026-10-20 11:30 UTCVendor advisory
- 2026-10-19 09:26 UTCEG score recompute
- 2026-10-19 09:26 UTCVendor advisory
- 2026-10-18 16:29 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-18 07:08 UTCEG score recompute
- 2026-10-18 07:08 UTCVendor advisory
- 2026-10-17 16:30 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-17 05:02 UTCEG score recompute
- 2026-10-17 05:02 UTCVendor advisory
- 2026-10-16 16:36 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-16 02:59 UTCEG score recompute
- 2026-10-16 02:59 UTCVendor advisory
- 2026-10-14 23:02 UTCEG score recompute
- 2026-10-14 23:02 UTCVendor advisory
- 2026-10-14 16:30 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-10-13 18:43 UTCEG score recompute
- 2026-10-13 18:43 UTCVendor advisory
- 2026-10-12 16:39 UTCEG score recompute
- 2026-10-12 16:39 UTCVendor advisory
- 2026-10-11 21:43 UTCEG score recompute
- 2026-10-08 17:06 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-30 19:14 UTCOSV refresh
- 2026-09-30 16:31 UTCEG score recompute
- 2026-09-30 15:01 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-27 13:42 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-26 15:56 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-24 14:01 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-23 13:46 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-18 19:25 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-16 05:11 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-12 02:10 UTCOSV refresh
- 2026-09-11 14:50 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-06 13:45 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-09-05 15:26 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-30 19:15 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-28 21:39 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-26 14:43 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-25 13:46 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-24 07:57 UTCOSV refresh
- 2026-08-15 01:28 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-08 16:35 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-08-08 04:19 UTCOSV refresh
- 2026-08-06 13:45 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-30 16:26 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-24 14:16 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-23 14:16 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-23 02:27 UTCEG score recompute
- 2026-07-22 21:22 UTCEG score recompute▲ 1.50
- 2026-07-22 21:22 UTCVendor advisory
- 2026-07-22 14:06 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-21 15:23 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-20 17:06 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-18 10:03 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-16 17:01 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-07-11 08:22 UTCOSV refresh
- 2026-07-08 15:13 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-30 23:21 UTCEPSS rescoreEPSS 92% · 99th percentile
- 2026-06-29 14:05 UTCEPSS rescoreEPSS 92% · 99th percentile
Publicly available exploits
(1 reference)Public exploit code is referenced for this CVE (1 GitHub PoC). Defenders should treat patch urgency accordingly.
- GitHub PoChex0punk/cont-flood-pocPublished Apr 12, 2024
PoC for CVE-2023-45288, continuation flood vulnerability
Open source ↗
Related CVEs(same product + same vendor + same CWE)
Same product
10 shownGo:golang.org/x/net/http2 · Debian:11:golang-golang-x-net · Debian:12:golang-golang-x-net
Same vendor
10 shownredhat:RHBA-2025:1772 · redhat:RHSA-2024:1616 · redhat:RHSA-2024:2068
Frequently asked(5)
What is CVE-2023-45288?
When was the CVE record for CVE-2023-45288 published?
Is CVE-2023-45288 actively exploited?
What is the CVSS score of CVE-2023-45288?
How do I remediate CVE-2023-45288?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-45288
Is Your Infrastructure Affected by CVE-2023-45288?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.