CVE-2026-40898

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.4% (33rd percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, NVD CVSS v3
Trending — 3 sources updated this week

Also known asEUVD-2026-34312 (ENISA EUVD) · GHSA-vvgj-x9jq-8cj9 (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
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 severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

quic-go is an implementation of the QUIC protocol in Go. Prior to version 0.59.1, an attacker can cause excessive memory allocation in quic-go's HTTP/3 client and server implementations by sending a QPACK-encoded HEADERS frame that decodes into a large trailer field section with many unique field names and/or large values. The implementation builds an http.Header for the corresponding http.Request or http.Response, while only enforcing limits on the size of the QPACK-compressed HEADERS frame, not on the decoded field section. This can lead to memory exhaustion. This is very similar to CVE-2025-64702. The difference is that this issue uses HTTP trailers, rather than HTTP headers, as the attack vector. A misbehaving or malicious peer can cause a denial-of-service (DoS) attack against quic-go's HTTP/3 servers or clients by triggering excessive memory allocation, potentially leading to crashes or resource exhaustion. This affects both servers and clients due to symmetric header construction. Version 0.59.1 enforces RFC 9114 decoded field section size limits for trailers as well. It incrementally decodes QPACK entries and checks the field section size after each entry, aborting the stream if an entry causes the limit to be exceeded.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
49
EG Risk 49/100

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.
Exploitation0.4% × 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
0.4%
EPSS %ILE
33rd
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 (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

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
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-29). 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: 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.

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

June 3, 2026

Last Modified

July 22, 2026

Advisory Details (2)

Auto-updated Jun 11, 2026
Patch available. Sources: github_release, github.
GitHub advisoryMentions a patch (unverified)

HTTP/3 QPACK Trailer Expansion Memory Exhaustion · Advisory · quic-go/quic-go · GitHub

https://github.com/quic-go/quic-go/security/advisories/GHSA-vvgj-x9jq-8cj9
GitHub release Patch Available

v0.59.1

Patch available: quic-go/quic-go v0.59.1

https://github.com/quic-go/quic-go/releases/tag/v0.59.1

Patch Availability(9)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatdevspaces/traefik-rhel9:17877567992026-09-01redhat
redhatcontainer-native-virtualization/kubevirt-apiserver-proxy-rhel9:17861257622026-08-11redhat
redhatansible-automation-platform-27/receptor-rhel9:17853894822026-08-04redhat
redhatreceptor-0:1.6.7-1.el9ap2026-08-04redhat
redhatansible-automation-platform-26/receptor-rhel9:17856321172026-08-04redhat
redhatcaddy-main-2.11.4-0.2.hum12026-07-15redhat
redhatrust-main-1.97.0-1.1.hum12026-07-11redhat
redhatcaddy-main-2.11.4-0.1.hum12026-06-11redhat
redhattrivy-main-0.69.3-1.2.hum12026-05-09redhat

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

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
golang-github-lucas-clemente-quic-go0.19.3-1 ... 0.59.0-2~bpo13+1 (30 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
golang-github-lucas-clemente-quic-go0.29.0-1 ... 0.59.0-2~bpo13+1 (23 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
golang-github-lucas-clemente-quic-go0.50.1-2 ... 0.59.0-2~bpo13+1 (9 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
golang-github-lucas-clemente-quic-go0.50.1-2 ... 0.59.0-2~bpo13+1 (9 versions)
  • every version on: no fix on record
—
Go(1)
PackageVulnerable rangeFix by version rangeDependents
github.com/quic-go/quic-go—
  • every version up to 0.59.1: fixed in 0.59.1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

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 10× in last 7d / 42× 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 237 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 137 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  2. 2026-10-30 10:06 UTCEG score recompute
  3. 2026-10-30 10:06 UTCVendor advisory
  4. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  5. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  6. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  7. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  8. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  9. 2026-10-25 14:30 UTCEG score recompute
  10. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  11. 2026-10-24 00:29 UTCEG score recompute
  12. 2026-10-24 00:29 UTCVendor advisory
  13. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  14. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  15. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  16. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  17. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  18. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  19. 2026-10-18 03:42 UTCEG score recompute
  20. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  21. 2026-10-17 14:45 UTCEG score recompute
  22. 2026-10-17 14:45 UTCVendor advisory
  23. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  24. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  25. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
Show 75 more
  1. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  2. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  3. 2026-10-12 16:09 UTCEG score recompute
  4. 2026-10-11 19:51 UTCEG score recompute
  5. 2026-10-11 17:04 UTCEG score recompute
  6. 2026-10-11 14:31 UTCEG score recompute
  7. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  8. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  9. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  10. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  12. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  13. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  14. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  16. 2026-10-03 12:09 UTCOSV refresh
  17. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  18. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  19. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  20. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  21. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  22. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  23. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  24. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  25. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  26. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  27. 2026-09-15 03:11 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  28. 2026-09-14 05:29 UTCEG score recompute
  29. 2026-09-14 05:29 UTCVendor advisory
  30. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  31. 2026-09-12 23:36 UTCOSV refresh
  32. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  33. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  34. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  35. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  36. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  37. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  38. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  39. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  40. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  41. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  42. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  43. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  44. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  45. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  46. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  47. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  48. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  49. 2026-08-25 03:36 UTCEG score recompute
  50. 2026-08-25 03:36 UTCVendor advisory
  51. 2026-08-24 01:13 UTCVendor advisory
  52. 2026-08-23 12:46 UTCEG score recompute
  53. 2026-08-23 12:46 UTCVendor advisory
  54. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  55. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  56. 2026-08-21 14:40 UTCEG score recompute
  57. 2026-08-21 14:40 UTCVendor advisory
  58. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  59. 2026-08-20 22:26 UTCVendor advisory
  60. 2026-08-20 10:00 UTCEG score recompute
  61. 2026-08-20 10:00 UTCVendor advisory
  62. 2026-08-19 17:03 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  63. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  64. 2026-08-17 15:59 UTCEG score recompute
  65. 2026-08-17 15:59 UTCVendor advisory
  66. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  67. 2026-08-17 03:43 UTCVendor advisory
  68. 2026-08-16 15:12 UTCEG score recompute
  69. 2026-08-16 15:12 UTCVendor advisory
  70. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  71. 2026-08-16 02:56 UTCEG score recompute
  72. 2026-08-16 02:56 UTCVendor advisory
  73. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.4% · 29th percentile
  74. 2026-08-15 14:40 UTCEG score recompute
  75. 2026-08-15 14:40 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-40898?
CVE-2026-40898 is a high-severity vulnerability; its CVE record was published on June 3, 2026. quic-go is an implementation of the QUIC protocol in Go. Prior to version 0.59.1, an attacker can cause excessive memory allocation in quic-go's HTTP/3 client and server implementations by sending a QPACK-encoded HEADERS frame that decodes into a large trailer field section with many unique field…
When was the CVE record for CVE-2026-40898 published?
The CVE record for CVE-2026-40898 was published on June 3, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of July 22, 2026; the record at its source may have been updated since.
Is CVE-2026-40898 actively exploited?
CVE-2026-40898 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (33rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-40898?
CVE-2026-40898 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-40898?
A fix for CVE-2026-40898 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-40898 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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