CVE-2026-32627 | cpp-httplib has a Silent TLS Certificate Verification Bypass on HTTPS Redirect via Proxy

Exp

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.37.2, when a cpp-httplib client is configured with a proxy and set_follow_location(true), any HTTPS redirect it follows will have TLS certificate and hostname verification silently disabled on the new connection. The client will accept any certificate presented by the redirect target — expired, self-signed, or forged — without raising an error or notifying the application. A network attacker in a position to return a redirect response can fully intercept the follow-up HTTPS connection, including any credentials or session tokens in flight. This vulnerability is fixed in 0.37.2.

Published: 2026-03-16 Last update: 2026-03-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-32627 is rated Exploit Available (51.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-32627

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-32627

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-14 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-32627

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.7 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 5.8 [email protected]
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 5.9 [email protected]

Weakness enumeration for CVE-2026-32627

OS Trackers for CVE-2026-32627

vendor priority summary link
debian not yet assigned CVE-2026-32627 not yet assigned priority: Debian including 1 source packages (cpp-httplib), 4 status rows across 4 suites (bookworm, forky, sid, trixie): open 2, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-32627
suse high — https://www.suse.com/security/cve/CVE-2026-32627/
ubuntu medium CVE-2026-32627 medium priority: Ubuntu including 1 source packages (cpp-httplib), 4 status rows across 4 suites (jammy, noble, questing, upstream): needs-triage 4. https://ubuntu.com/security/CVE-2026-32627

Affected software / configurations for CVE-2026-32627

Vendor Product Version Raw CPE
yhirose cpp-httplib < 0.37.2 cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*

References for CVE-2026-32627

cvelogic Threat Intelligence