CVE-2009-0585: Integer overflow in the soup_base64_encode function in soup-misc.c in libsoup 2.x.x before 2.2.x, and 2.x befo

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HIGH 7.5DOWNGRADE

CVE-2009-0585 is a high-severity flaw (CVSS 7.5) affecting libsoup. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Integer overflow in the soup_base64_encode function in soup-misc.c in libsoup 2.x.x before 2.2.x, and 2.x before 2.24, allows context-dependent attackers to execute arbitrary code via a long string that is converted to a base64 representation.

Why this priority

High severity
EPSS top 9%: very likely to be exploited

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	4.0% (top 9%)
CISA exploited list	No
Weakness	CWE-189
Published	2009-03-14
Last modified	2026-06-16

Publisher (CNA): Red Hat, Inc. · Vendor: joe shaw

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2009-03-14 18:30 UTCPublished CVE record published
2026-06-16 23:05 UTCUpdated Record last modified

joe shaw libsoup DOWNGRADE

Affected: 2.1 · 2.23.1 · 2.23.6 · 2.23.91 · 2.23.92

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.1

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 2.1 (Debian / Ubuntu)

apt-cache madison libsoup sudo apt install libsoup=<VERSION_BEFORE_2.1> sudo apt-mark hold libsoup

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list libsoup sudo dnf downgrade libsoup-<VERSION_BEFORE_2.1> sudo dnf versionlock add libsoup

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.

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-2009-0585?

libsoup: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2009-0585 being exploited?

CVE-2009-0585 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-2009-0585 affect?

CVE-2009-0585 affects libsoup. Severity is high (CVSS 7.5). Integer overflow in the soup_base64_encode function in soup-misc.c in libsoup 2.x.x before 2.2.x, and 2.x before 2.24, allows context-dependent attackers to execute arbitrary code via a long string that is converted to a base64 representati

How urgent is CVE-2009-0585?

Priority 49/100. High severity; EPSS top 9%: very likely to be exploited

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References

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