CVE-2026-5244 (GCVE-0-2026-5244)
Vulnerability from cvelistv5 – Published: 2026-04-02 08:00 – Updated: 2026-04-02 13:31 X_Open Source
VLAI?
Title
Cesanta Mongoose TLS 1.3 mongoose.c mg_tls_recv_cert heap-based overflow
Summary
A vulnerability has been found in Cesanta Mongoose up to 7.20. This affects the function mg_tls_recv_cert of the file mongoose.c of the component TLS 1.3 Handler. Such manipulation of the argument pubkey leads to heap-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 7.21 mitigates this issue. The name of the patch is 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
Severity ?
Assigner
References
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Cesanta | Mongoose |
Affected:
7.0
Affected: 7.1 Affected: 7.2 Affected: 7.3 Affected: 7.4 Affected: 7.5 Affected: 7.6 Affected: 7.7 Affected: 7.8 Affected: 7.9 Affected: 7.10 Affected: 7.11 Affected: 7.12 Affected: 7.13 Affected: 7.14 Affected: 7.15 Affected: 7.16 Affected: 7.17 Affected: 7.18 Affected: 7.19 Affected: 7.20 Unaffected: 7.21 cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:* |
Credits
the_evilsocket (VulDB User)
VulDB
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Sightings
| Author | Source | Type | Date |
|---|
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.
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