LOWVulnerability

CVE-2026-77640

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.

Properties

severity
LOW
score
3.7
epss_score
0.00215
cve_id
CVE-2026-77640
vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
published_at
2026-08-20T21:17:11.373
last_modified
2026-09-03T17:37:43.450
epss_percentile
0.11775

Related Entities (3)

ENRICHED_BY (1)

[Source]FIRST EPSS

HAS_WEAKNESS (1)

[Weakness]Improper Validation of Specified Quantity in Input

DESCRIBED_BY (1)

[Source]NVD

Explore deeper with Ninja Signal's threat intelligence graph

CVE-2026-77640 — Ninja Signal Threat Intelligence | Ninja Signal