CVE-2025-49812 (GCVE-0-2025-49812)

Vulnerability from cvelistv5 – Published: 2025-07-10 16:58 – Updated: 2025-11-04 21:11
VLAI
Title
Apache HTTP Server: mod_ssl TLS upgrade attack
Summary
In some mod_ssl configurations on Apache HTTP Server versions through to 2.4.63, an HTTP desynchronisation attack allows a man-in-the-middle attacker to hijack an HTTP session via a TLS upgrade. Only configurations using "SSLEngine optional" to enable TLS upgrades are affected. Users are recommended to upgrade to version 2.4.64, which removes support for TLS upgrade.
Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-07-11 16:05 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache HTTP Server Affected: 0 , ≤ 2.4.63 (semver)
Create a notification for this product.
Credits
Robert Merget (Technology Innovation Institute) Nurullah Erinola (Ruhr University Bochum) Marcel Maehren (Ruhr University Bochum) Lukas Knittel (Ruhr University Bochum) Sven Hebrok (Paderborn University) Marcus Brinkmann (Ruhr University Bochum) Juraj Somorovsky (Paderborn University) Jörg Schwenk (Ruhr University Bochum)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • 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.
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  • 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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