CVE-2026-53524

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 81% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Elevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module's WebSocket permessage-deflate decompression function relay_websocket_inflate() has no upper bound on output size. An authenticated relay user can send a small compressed WebSocket frame (~100 bytes) that decompresses to gigabytes, exhausting all server memory and crashing the entire WeeChat process. The api protocol enables permessage-deflate and requires authentication before WebSocket upgrade. Version 4.9.1 patches the issue.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
45(Track)
EG Risk 45/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
19%
KEV
Not listed

Published

August 21, 2026

Last Modified

September 9, 2026

Advisory Details (1)

Auto-updated Aug 21, 2026
Patch available. Sources: github.
github Patch Available

Decompression Bomb in Relay WebSocket (DoS) · Advisory · weechat/weechat · GitHub

https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
weechat3.8-1 ... 4.9.5-1 (20 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
weechat4.10.0-1 ... 4.9.5-1 (8 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
weechat4.6.3-1, 4.7.2-1, 4.8.1-1, 4.9.0-14.9.3-1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 10× in last 7d / 46× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

  1. 2026-09-19 00:13 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 00:06 UTCEG score recompute
  4. 2026-09-16 22:41 UTCEG score recompute
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-15 22:01 UTCEG score recompute
  8. 2026-09-13 21:46 UTCEG score recompute
  9. 2026-09-13 16:47 UTCEPSS rescore
  10. 2026-09-12 21:39 UTCEG score recompute
  11. 2026-09-11 21:32 UTCEG score recompute
  12. 2026-09-11 14:53 UTCEPSS rescore
  13. 2026-09-10 21:25 UTCEG score recompute
  14. 2026-09-10 09:35 UTCEPSS rescore
  15. 2026-09-09 02:42 UTCEG score recompute
  16. 2026-09-08 22:01 UTCEPSS rescore
  17. 2026-09-08 02:35 UTCEG score recompute
  18. 2026-09-07 16:01 UTCEPSS rescore
  19. 2026-09-07 02:29 UTCEG score recompute
  20. 2026-09-06 13:47 UTCEPSS rescore
  21. 2026-09-06 02:09 UTCEG score recompute
  22. 2026-09-05 02:03 UTCEG score recompute
  23. 2026-09-04 05:06 UTCEPSS rescore
  24. 2026-09-03 01:48 UTCEG score recompute
  25. 2026-09-02 14:12 UTCEPSS rescore
Show 21 more
  1. 2026-09-02 01:40 UTCEG score recompute
  2. 2026-09-01 13:54 UTCEPSS rescore
  3. 2026-09-01 04:40 UTCEPSS rescore
  4. 2026-08-31 01:18 UTCEG score recompute
  5. 2026-08-30 19:17 UTCEPSS rescore
  6. 2026-08-30 01:22 UTCEPSS rescore
  7. 2026-08-29 01:02 UTCEG score recompute
  8. 2026-08-28 21:41 UTCEPSS rescore
  9. 2026-08-27 20:52 UTCEG score recompute
  10. 2026-08-27 14:25 UTCEPSS rescore
  11. 2026-08-26 20:46 UTCEG score recompute
  12. 2026-08-26 14:46 UTCEPSS rescore
  13. 2026-08-25 20:37 UTCEG score recompute
  14. 2026-08-25 13:49 UTCEPSS rescore
  15. 2026-08-24 20:27 UTCEG score recompute
  16. 2026-08-24 20:12 UTCEG score recompute
  17. 2026-08-23 23:39 UTCEG score recompute
  18. 2026-08-23 00:19 UTCEPSS rescore
  19. 2026-08-21 23:26 UTCEG score recompute
  20. 2026-08-21 22:29 UTCEG score recompute
  21. 2026-08-21 22:29 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-53524?
CVE-2026-53524 is a medium vulnerability published on August 21, 2026. WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module's WebSocket permessage-deflate decompression function relaywebsocketinflate() has no upper bound on output size. An authenticated relay user can send a small compressed…
When was CVE-2026-53524 disclosed?
CVE-2026-53524 was first published in the National Vulnerability Database on August 21, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53524 actively exploited?
CVE-2026-53524 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 80.8% of all scored CVEs.
What is the CVSS score of CVE-2026-53524?
CVE-2026-53524 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-53524?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53524, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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