CVE-2026-77640

mediumpriority · track · 21EPSS 0.004 · 32 %ileDEUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.38% (32nd) EPSS
CVSS 5.3 · medium
Is it mine?
3 products
Check your exposure
Who says so?
2 sources
cert_bund · nvd

EPSS · scored 2026-10-27

tor before 0.4.9.9 was prone to an infinite loop when decompressing a truncated zlib/gzip stream with done=1. A truncated stream never reaches Z_STREAM_END, causing zlib to return Z_BUF_ERROR with no input remaining, which buf_add_compress() mistook for a full output buffer and retried forever. Fixed by returning TOR_COMPRESS_ERROR in that case so the caller can abort cleanly. This is TROVE-2026-021.

01

cvss

Technical severity, 0–10. One row per scoring source.

5.3
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.7–5.3

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4
v3.13.7lowCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · cve@mitre.org USexploitability 2.2 · impact 1.4
v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1284US
04

affected products (3)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-2959Tor: Mehrere SchwachstellenDeutsch2026-08-20csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Tor ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, Informationen offenzulegen oder einen Denial-of-Service-Zustand herbeizuführen.

06

sources

Which sources assert this record, and when.

cert_bundnvdNVDCVE.orgMITRE
published 2026-08-20modified 2026-10-18
07

references (1) nvd

External citations — patches, advisories, analysis.

scry

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