CVE-2026-77622 json
Sliver: Unauthenticated Memory Exhaustion Denial of Service in Sliver HTTP(S) Listener PNG Decoder
published 2026-10-15 24 d ago modified 2026-11-05 3 d ago also GHSA-663m-7x7m-g4fw , GO-2026-6777 , EUVD-2026-117798
- cvss
- 8.2
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
Sliver is a command and control framework. Prior to 1.7.6, an HTTP(S) listener using the PNG encoder accepts attacker-controlled PNG dimensions without an effective decoded-size or pixel limit in util/encoders/images.go, while the listener nonce space implemented in server/encoders/encoders.go is small enough to search remotely. An unauthenticated attacker who identifies a valid nonce can submit a highly compressed image to PNGEncoder.Decode, where it expands during png.Decode, exhausting server memory and causing a complete loss of availability. This vulnerability is fixed in 1.7.6.
Patch / fix
- go github.com/BishopFox/sliver 1.7.6
- go github.com/bishopfox/sliver 1.7.6
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/BishopFox/sliver | <1.7.6 |
1.7.6 |
| go | github.com/bishopfox/sliver | <1.7.6 |
1.7.6 |
Affected products
- BishopFox sliver
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
Sources
- CVE List CVE-2026-77622
- GitHub Advisory GHSA-663m-7x7m-g4fw
- NVD CVE-2026-77622
- OSV GO-2026-6777
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