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TI-2025-11595 Aliases CVE-2025-12642GHSA-fvx8-q97q-cw73

HTTP Header Smuggling via Trailer Merge

Priority LOW 37CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing. This behavior can be exploited to conduct HTTP Header Smuggling attacks. Successful exploitation may allow an attacker to: * Bypass access control rules * Inject unsafe input into backend logic that trusts request headers * Execute HTTP Request Smuggling attacks under some conditions This issue affects lighttpd1.4.80

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00368 30th percentileScored 2026-11-07
Fix Fixed lighttpd (lighttpd): 1.4.81

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
lighttpdlighttpd1.4.80 to before 1.4.811.4.81Patch availableCNA
  • lighttpd Vendorlighttpd Affected 1.4.80 to before 1.4.81 Fixed in 1.4.81 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:lighttpd:lighttpd:1.4.80:*:*:*:*:*:*:*1.4.80Vulnerablelighttpd
  • cpe:2.3:a:lighttpd:lighttpd:1.4.80:*:*:*:*:*:*:* Versions 1.4.80 Vulnerable ·lighttpd

Remediation

  • Fix · CNA lighttpd (lighttpd) Fixed in 1.4.81

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-12642
  2. 2026-10-03 Alias added: GHSA-fvx8-q97q-cw73

References

Patch 1

  • TI-2019-08280 lighttpd before 1.4.54 has a signed integer overflow, which might allow remote attackers… CVSS 3.0CRITICAL 9.8
  • TI-2014-01841 SQL injection vulnerability in mod_mysql_vhost.c in lighttpd before 1.4.35 allows remote… CVSS 3.1CRITICAL 9.8
  • TI-2022-12909 Lighttpd 1.4.56 through 1.4.58 allows a remote attacker to cause a denial of service (CPU… CVSS 3.1HIGH 7.5
  • TI-2018-13505 An issue was discovered in mod_alias_physical_handler in mod_alias.c in lighttpd before… CVSS 3.1HIGH 7.5
  • TI-2014-01842 Multiple directory traversal vulnerabilities in (1) mod_evhost and (2) mod_simple_vhost… CVSS 2.0MEDIUM 5.0
  • TI-2013-04004 lighttpd before 1.4.33 does not check the return value of the (1) setuid, (2) setgid, or… CVSS 2.0HIGH 7.6
See all 34 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences