CVE-2026-8925: The curl logic that works with SASL authentication could end up cleaning up the GSASL context twice without

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CRITICAL 9.8REMOTEUPGRADE

CVE-2026-8925 is a critical-severity flaw (CVSS 9.8) affecting curl. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing the pointer in between, making it `free()` the same pointer twice.

Why this priority

Critical severity
Public exploit reference
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.1% (top 35%)
CISA exploited list	No
Weakness	CWE-415
Published	2026-07-03
Last modified	2026-09-15

Publisher (CNA): curl · Vendor: haxx

Last updated 2026-09-15 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-07-03 07:16 UTCPublished CVE record published
2026-09-15 07:16 UTCUpdated Record last modified

haxx curl UPGRADE

Affected: >= 8.15.0 and < 8.21.0

Fixed in: 8.21.0

Safe to downgrade to: a release before 8.15.0

1. Check installed version

apt-cache policy curl || rpm -q curl || curl --version

2. UPGRADE to 8.21.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade curl

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade curl

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 8.15.0 (Debian / Ubuntu)

apt-cache madison curl sudo apt install curl=<VERSION_BEFORE_8.15.0> sudo apt-mark hold curl

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list curl sudo dnf downgrade curl-<VERSION_BEFORE_8.15.0> sudo dnf versionlock add curl

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Exact fixes by distribution

Fedora 46 · rubygem-mechanize · FIXED · 2.14.2-1.fc46 · FEDORA-2026-d2e3b5fc5d · source

sudo dnf upgrade --advisory=FEDORA-2026-d2e3b5fc5d

Fedora ELN · opkssh · FIXED · 0.19.1-1.eln159 · FEDORA-2026-45a9706969 · source

sudo dnf upgrade --advisory=FEDORA-2026-45a9706969

Ubuntu 20.04 · curl · NOT AFFECTED

Ubuntu 22.04 · curl · FIXED · 7.81.0-1ubuntu1.25

sudo apt update && sudo apt install --only-upgrade curl dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "7.81.0-1ubuntu1.25" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · curl · FIXED · 8.5.0-2ubuntu10.10

sudo apt update && sudo apt install --only-upgrade curl dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "8.5.0-2ubuntu10.10" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 25.10 · curl · FIXED · 8.14.1-2ubuntu1.4

sudo apt update && sudo apt install --only-upgrade curl dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "8.14.1-2ubuntu1.4" && echo PATCHED || echo STILL-VULNERABLE

Debian 12 · curl · NOT AFFECTED

Debian 13 · curl · NOT AFFECTED

RHEL 10 · curl · NOT AFFECTED

RHEL 6 · curl · NOT AFFECTED

RHEL 7 · curl · NOT AFFECTED

RHEL 8 · curl · NOT AFFECTED

RHEL 9 · curl · NOT AFFECTED

Alpine 3.23 · curl · FIXED · curl-8.22.0-r0

apk add --upgrade curl apk info -v curl

Alpine 3.24 · curl · FIXED · curl-8.21.0-r0

apk add --upgrade curl apk info -v curl

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2026-2132 · source

sudo dnf update --advisory=ALAS2023-2026-2132

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-8925?

curl: upgrade to 8.21.0. Exact commands for each OS are on this page.

Is CVE-2026-8925 being exploited?

CVE-2026-8925 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-8925 affect?

CVE-2026-8925 affects curl. Severity is critical (CVSS 9.8). The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing the pointer in between, making it `free()` the same pointer twice.

How urgent is CVE-2026-8925?

Priority 64/100. Critical severity; Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Software pages

curl vulnerabilities

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References

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CVE-2026-8925: The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without