CVE-2026-77640 (GCVE-0-2026-77640)
Vulnerability from cvelistv5
Published
2026-08-20 21:02
Modified
2026-08-21 20:08
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-1284 - Improper Validation of Specified Quantity in Input
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| torproject | Tor |
Version: 0.2.6.1-alpha < 0.4.9.9 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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