CVE-2025-5372VulnerabilityPublished 10 Dec 2025Updated 1 Sep 2026

Red Hat Security Advisory: libssh security update

Affects Red Hat libsshSource GCVE Database

Authoritative record:CVE-2025-5372· Medium 5.0

Not known to be exploited · CVSS 5.0 Medium.

Data as of 26 Oct 2026, 09:15 UTC

CVSS 3.1 base score

5.0Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L

Exploitation evidence

Disclosed: evidence found.
CVE published 4 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Red Hat Product Security Red Hat	Affected Red Hat Red Hat Enterprise Linux Red Hat Enterprise Linux AppStream (v. 8) Red Hat Enterprise Linux BaseOS (v. 8) aarch64 Red Hat Enterprise Linux AppStream E4S (v.9.0) Red Hat Enterprise Linux BaseOS E4S (v.9.0) src Red Hat Enterprise Linux AppStream AUS (v.8.4) Red Hat Enterprise Linux BaseOS AUS (v.8.4) Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) Red Hat Enterprise Linux AppStream E4S (v.8.8) Red Hat Enterprise Linux BaseOS E4S (v.8.8) Red Hat Enterprise Linux AppStream TUS (v.8.8)	Fixed in–

AI-suggested

Red Hat has released updated libssh packages for Red Hat Enterprise Linux 8 to address this vulnerability. Users should apply the security update as described in Red Hat advisory RHSA-2025:21977 and the related article https://access.redhat.com/articles/11258. This update fixes the incorrect return code handling in ssh_kdf(). No additional mitigation steps are indicated by the vendor.

Description

libssh is a library which implements the SSH protocol. It can be used to implement client and server applications. Security Fix(es): * libssh: Incorrect Return Code Handling in ssh_kdf() in libssh (CVE-2025-5372) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Impact

The vulnerability may cause improper handling of return codes in the key derivation function within libssh, potentially leading to incorrect cryptographic behavior. The exact impact is not detailed beyond the moderate severity rating provided by Red Hat. There are no known exploits in the wild at this time.

Summary

The vulnerability CVE-2025-5372 in libssh concerns incorrect return code handling in the ssh_kdf() function, which is part of the key derivation process in the SSH protocol implementation. This flaw could potentially affect the correctness of cryptographic operations relying on this function. Red Hat has released updated libssh packages for Red Hat Enterprise Linux 8 across multiple architectures to fix this issue. The advisory classifies the security impact as moderate. No detailed CVSS vector or score is available. The update is documented in Red Hat advisory RHSA-2025:21977.

CWE-682Incorrect Calculation (opens in a new tab)
Pillar weaknessLikelihood of exploit: High
The product performs a calculation that generates incorrect or unintended results that are later used in security-critical decisions or resource management.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Implementation
Understand your programming language's underlying representation and how it interacts with numeric calculation. Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, "not-a-number" calculations, and how your language handles numbers…
Implementation · Input Validation
Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
Implementation
Use the appropriate type for the desired action. For example, in C/C++, only use unsigned types for values that could never be negative, such as height, width, or other numbers related to quantity.
Attack patterns
Integer Attacks (opens in a new tab)
Pointer Manipulation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 12 Jul 2026, 09:34 UTC

WeaknessesCWE-682

Technical details

References

Community reviews

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