CVE-2019-15900: An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD

Q: How do I fix CVE-2019-15900?

doas: upgrade to 6.2. Exact commands for each OS are on this page.

Q: Is CVE-2019-15900 being exploited?

CVE-2019-15900 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2019-15900 affect?

CVE-2019-15900 affects doas. Severity is critical (CVSS 9.8). An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in s

Q: How urgent is CVE-2019-15900?

Priority 60/100. Critical severity; Remotely exploitable, no login, no user action

This week

CRITICAL 9.8REMOTEUPGRADE

CVE-2019-15900 is a critical-severity flaw (CVSS 9.8) affecting doas. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in some cases returned success even if sscanf failed. The result was that, instead of reporting that the supplied username or group name did not exist, it would execute the command as root.

Why this priority

Critical severity
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	2.1% (top 18%)
CISA exploited list	No
Weakness	CWE-252, CWE-754, CWE-863, CWE-908
Published	2019-10-18
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: doas project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-10-18 16:15 UTCPublished CVE record published
2026-06-17 02:21 UTCUpdated Record last modified

doas project doas UPGRADE

Affected: < 6.2

Fixed in: 6.2

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to 6.2 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade doas

Note

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

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-2019-15900?

doas: upgrade to 6.2. Exact commands for each OS are on this page.

Is CVE-2019-15900 being exploited?

CVE-2019-15900 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-2019-15900 affect?

CVE-2019-15900 affects doas. Severity is critical (CVSS 9.8). An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in s

How urgent is CVE-2019-15900?

Priority 60/100. Critical severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2019-15901 HIGH 8.8 UPGRADE An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD

References

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