Vulnerability-Lookup

GHSA-223H-642R-2F6V

Vulnerability from github – Published: 2026-07-22 18:32 – Updated: 2026-07-22 18:32

Details

A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated "code verifier" lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer the pseudo-random number generator (PRNG) seed to predict or reconstruct the code verifier string, allowing an attacker to bypass PKCE protections and successfully impersonate the client during the OAuth 2.0 authorization flow.

Severity

6.8 (Medium)


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

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  "id": "GHSA-223h-642r-2f6v",
  "modified": "2026-07-22T18:32:39Z",
  "published": "2026-07-22T18:32:38Z",
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      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2504432"
    },
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      "type": "WEB",
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    }
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}

CVE-2026-16615 (GCVE-0-2026-16615)

Vulnerability from cvelistv5 – Published: 2026-07-22 16:12 – Updated: 2026-07-22 16:43

Title

Librest: weak random number generation in pkce implementation

Summary

Severity

6.8 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Assigner

redhat

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-16615	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2504432	issue-trackingx_refsource_REDHAT
https://gitlab.gnome.org/GNOME/librest/-/issues/25

Impacted products

1 product

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10

Date Public

2026-02-28 00:00

Credits

Red Hat would like to thank Cole Blakley for reporting this issue.

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-223H-642R-2F6V

CVE-2026-16615 (GCVE-0-2026-16615)

Tags

Sightings

Nomenclature