CVE-2026-9546

highpriority · track · 0EPSS 0.007 · 51 %ileDEEUFRUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.65% (51st) EPSS
CVSS 7.5 · high
Is it mine?
22 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · cert_bund · certfr

EPSS · scored 2026-10-27

A vulnerability in libcurl caused the HTTP `Referer:` header to persist even when explicitly cleared. While the documentation states that passing NULL to `CURLOPT_REFERER` suppresses the header, the option failed to clear the internal state. As a result, the previous referrer string was erroneously reused and sent in subsequent requests, potentially leaking sensitive information to unintended servers.

01

cvss

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

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondaryexploitability 3.9 · impact 3.6
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

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

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-200US
04

affected products (22)

Products and version ranges known to be affected.

showing 20 of 22
05

advisories (4)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-2052cURL: Mehrere SchwachstellenDeutsch2026-06-23csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um Sicherheitsvorkehrungen zu umgehen, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand oder eine Speicherbeschädigung zu verursachen.

  • CERTFR-2026-AVI-1385Multiples vulnérabilités dans les produits VMwareFrançais2026-10-26vendor · certfrFR
  • CERTFR-2026-AVI-1390Multiples vulnérabilités dans Tenable Network MonitorFrançais2026-10-27vendor · certfrFR
  • CURL-CVE-2026-9546sending old referer2026-06-24vendor · osvUS

    A vulnerability in libcurl caused the HTTP `Referer:` header to persist even when explicitly cleared. While the documentation states that passing NULL to `CURLOPT_REFERER` suppresses the header, the option failed to clear the internal state. As a result, the previous referrer string was erroneously reused and sent in subsequent requests, potentially leaking sensitive information to unintended servers.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcert_bundcertfrosvNVDCVE.orgMITRE
published 2026-07-03modified 2026-09-15
08

references (9)

External citations — patches, advisories, analysis.

scry

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