CVE-2010-1256: Unspecified vulnerability in Microsoft IIS 6.0, 7.0, and 7.5, when Extended Protection for Authentication is e

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HIGH 8.5WATCHLISTDOWNGRADE

CVE-2010-1256 is a high-severity flaw (CVSS 8.5) affecting internet information server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Unspecified vulnerability in Microsoft IIS 6.0, 7.0, and 7.5, when Extended Protection for Authentication is enabled, allows remote authenticated users to execute arbitrary code via unknown vectors related to "token checking" that trigger memory corruption, aka "IIS Authentication Memory Corruption Vulnerability."

Why this priority

High severity
EPSS top 2%: very likely to be exploited
On your watchlist

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

Risk facts

CVSS score	8.5 (High)
EPSS exploit chance	28.2% (top 2%)
CISA exploited list	No
Weakness	CWE-94
Published	2010-06-08
Last modified	2026-06-16

Publisher (CNA): Microsoft Corporation · Vendor: microsoft

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

Am I affected?

Timeline

2010-06-08 20:30 UTCPublished CVE record published
2026-06-16 23:17 UTCUpdated Record last modified

microsoft internet information server DOWNGRADE

Affected: 6.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 6.0

1. Check installed version

apt-cache policy internet-information-server || rpm -q internet-information-server || internet-information-server --version

2. No fixed release: DOWNGRADE to a release before 6.0 (Debian / Ubuntu)

apt-cache madison internet-information-server sudo apt install internet-information-server=<VERSION_BEFORE_6.0> sudo apt-mark hold internet-information-server

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

dnf --showduplicates list internet-information-server sudo dnf downgrade internet-information-server-<VERSION_BEFORE_6.0> sudo dnf versionlock add internet-information-server

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-2010-1256?

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

Is CVE-2010-1256 being exploited?

CVE-2010-1256 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-2010-1256 affect?

CVE-2010-1256 affects internet information server. Severity is high (CVSS 8.5). Unspecified vulnerability in Microsoft IIS 6.0, 7.0, and 7.5, when Extended Protection for Authentication is enabled, allows remote authenticated users to execute arbitrary code via unknown vectors related to "token checking" that trigger m

How urgent is CVE-2010-1256?

Priority 59/100. High severity; EPSS top 2%: very likely to be exploited; On your watchlist

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References

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