GNOME libsoup SoupAuthDomainDigest nonce re-use

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in GNOME libsoup. This affects the function SoupAuthDomainDigest. Such manipulation leads to nonce re-use. This vulnerability is referenced as CVE-2026-3099. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in GNOME libsoup (affected version not known). Affected by this issue is the function SoupAuthDomainDigest. The manipulation with an unknown input leads to a nonce re-use vulnerability. Using CWE to declare the problem leads to CWE-323. Nonces should be used for the present occasion and only once. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A flaw was found in Libsoup. The server-side digest authentication implementation in the SoupAuthDomainDigest class does not properly track issued nonces or enforce the required incrementing nonce-count (nc) attribute. This vulnerability allows a remote attacker to capture a single valid authentication header and replay it repeatedly. Consequently, the attacker can bypass authentication and gain unauthorized access to protected resources, impersonating the legitimate user.

The advisory is shared for download at access.redhat.com. This vulnerability is handled as CVE-2026-3099 since 02/24/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 03/23/2026). The MITRE ATT&CK project declares the attack technique as T1600.001.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.0
VulDB Temp Score: 5.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.3
NVD Vector: 🔒

CNA Base Score: 5.8
CNA Vector (redhat): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Nonce re-use
CWE: CWE-323
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

02/24/2026 CVE reserved
03/12/2026 +16 days Advisory disclosed
03/12/2026 +0 days VulDB entry created
03/23/2026 +11 days VulDB entry last update

Sourcesinfo

Vendor: gnome.org

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2026-3099 (🔒)
GCVE (CVE): GCVE-0-2026-3099
GCVE (VulDB): GCVE-100-350660

Entryinfo

Created: 03/12/2026 15:36
Updated: 03/23/2026 15:56
Changes: 03/12/2026 15:36 (60), 03/17/2026 10:31 (1), 03/23/2026 15:56 (11)
Complete: 🔍
Cache ID: 216::103

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