Apache HTTP Server: mod_ssl TLS upgrade attack
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Apache Software Foundation | Apache HTTP Server | unaffected |
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No data.
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Http Server | — |
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4270-1 | apache2 security update |
EUVD |
EUVD-2025-21016 | 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. |
Ubuntu USN |
USN-7639-1 | Apache HTTP Server vulnerabilities |
Ubuntu USN |
USN-7639-2 | Apache HTTP Server vulnerabilities |
Ubuntu USN |
USN-8338-1 | Apache HTTP Server vulnerabilities |
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.748% probability within 30 days)
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| First Time appeared |
Apache
Apache http Server |
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| CPEs | cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Apache
Apache http Server |
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epss
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epss
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cvssV3_1
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ssvc
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threat_severity
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cvssV3_1
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epss
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| Description | 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. | |
| Title | Apache HTTP Server: mod_ssl TLS upgrade attack | |
| Weaknesses | CWE-287 | |
| References |
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