CVE-2025-66570

criticalpriority · track · 39OT risk · elevatedEPSS 0.003 · 27 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.34% (27th) EPSS
CVSS 9.8 · critical
Is it mine?
2 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · suse_csaf

EPSS · scored 2026-10-27

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-visible metadata, logging, and authorization decisions. An attacker can inject headers named REMOTE_ADDR, REMOTE_PORT, LOCAL_ADDR, LOCAL_PORT that are parsed into the request header multimap via read_headers() in httplib.h (headers.emplace), then the server later appends its own internal metadata using the same header names in Server::process_request without erasing duplicates. Because Request::get_header_value returns the first entry for a header key (id == 0) and the client-supplied headers are parsed before server-inserted headers, downstream code that uses these header names may inadvertently use attacker-controlled values. Affected files/locations: cpp-httplib/httplib.h (read_headers, Server::process_request, Request::get_header_value, get_header_value_u64) and cpp-httplib/docker/main.cc (get_client_ip, nginx_access_logger, nginx_error_logger). Attack surface: attacker-controlled HTTP headers in incoming requests flow into the Request.headers multimap and into logging code that reads forwarded headers, enabling IP spoofing, log poisoning, and authorization bypass via header shadowing. This vulnerability is fixed in 0.27.0.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.aarch64 as component of SUSE Linux Enterprise Server 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.aarch64 as component of SUSE Linux Enterprise Server for SAP applications 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.ppc64le as component of SUSE Linux Enterprise Server 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.ppc64le as component of SUSE Linux Enterprise Server for SAP applications 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.s390x as component of SUSE Linux Enterprise Server 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.s390x as component of SUSE Linux Enterprise Server for SAP applications 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.x86_64 as component of SUSE Linux Enterprise Server 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.x86_64 as component of SUSE Linux Enterprise Server for SAP applications 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedcpp-httplib-devel-0:0.22.0-160000.3.1.aarch64 as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedcpp-httplib-devel-0:0.22.0-160000.3.1.ppc64le as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedcpp-httplib-devel-0:0.22.0-160000.3.1.s390x as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedcpp-httplib-devel-0:0.22.0-160000.3.1.x86_64 as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.aarch64 as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.ppc64le as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.s390x as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibcpp-httplib0_22-0:0.22.0-160000.3.1.x86_64 as component of openSUSE Leap 16.0suse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

02

cvss

Technical severity, 0–10. One row per scoring source.

10.0
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · ENISA EU
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · security-advisories@github.comexploitability 3.9 · impact 5.8
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · SUSE Product Security
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-290USCWE-345USCWE-807US
05

affected products (2)

Products and version ranges known to be affected.

06

advisories (2)

Vendor and ecosystem advisories describing this.

07

also known as (2)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdsuse_csafNVDCVE.orgMITRE
published 2025-12-05modified 2026-06-17
09

references (7)

External citations — patches, advisories, analysis.

scry

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