Security Digest · Vulnerability record
CVE-2024-39223: Missing key verification in gost
An authentication bypass in the SSH service of gost v2.11.5 allows attackers to intercept communications via setting the HostKeyCallback function to ssh.InsecureIgnoreHostKey
CVSS 9.8 Critical EPSS 0.7% · p52
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7%, percentile 52: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 52% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
github.com/ginuerzh/gost(Go) <= 2.11.5, no fixed version listed. Check your lockfile, including transitive dependencies.
What it is
An authentication bypass in the SSH service of gost v2.11.5 allows attackers to intercept communications via setting the HostKeyCallback function to ssh.InsecureIgnoreHostKey
From the GitHub advisory
An authentication bypass in the SSH service of gost v2.11.5 allows attackers to intercept communications via setting the HostKeyCallback function to ssh.InsecureIgnoreHostKey
Weakness type: CWE-639, CWE-289.
Product: github.com/ginuerzh/gost (Go) · Assigned by: mitre · Published: 2024-07-03
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Go | github.com/ginuerzh/gost | <= 2.11.5 | none listed |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| n/a | n/a | see vendor advisory |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.70% probability of exploitation activity in the next 30 days; percentile 52.
Timeline
- — CVE record published by mitre
- — GitHub-reviewed advisory GHSA-8wxx-35qc-vp6r published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-8wxx-35qc-vp6r github.com
- CVE.org record CVE-2024-39223 cve.org
- NVD entry CVE-2024-39223 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- gist.github.com gist.github.com