CVE-2026-70105: Improper input validation in Microsoft Office Word allows an unauthorized attacker to disclose information ove

This month

MEDIUM 6.5WATCHLISTMITIGATEDOWNGRADEMITIGATE

CVE-2026-70105 is a medium-severity flaw (CVSS 6.5) affecting microsoft 365, office, office 2021. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Improper input validation in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.

Why this priority

On your watchlist

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

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	1.0% (top 38%)
CISA exploited list	No
Weakness	CWE-20
Published	2026-08-20
Last modified	2026-10-26

Publisher (CNA): Microsoft Corporation · Vendor: microsoft

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-20 22:18 UTCPublished CVE record published
2026-10-26 10:10 UTCUpdated Record last modified

microsoft microsoft 365 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy microsoft-365 || rpm -q microsoft-365 || microsoft-365 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

microsoft office DOWNGRADE

Affected: 2019

Fixed in: no fixed release known

Safe to downgrade to: a release before 2019

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 2019 (Debian / Ubuntu)

apt-cache madison office sudo apt install office=<VERSION_BEFORE_2019> sudo apt-mark hold office

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

dnf --showduplicates list office sudo dnf downgrade office-<VERSION_BEFORE_2019> sudo dnf versionlock add office

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.

microsoft office 2021 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy office-2021 || rpm -q office-2021 || office-2021 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

microsoft office 2021 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy office-2021 || rpm -q office-2021 || office-2021 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

microsoft office 2024 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy office-2024 || rpm -q office-2024 || office-2024 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

microsoft office 2024 MITIGATE

Affected: all versions

Fixed in: no fixed release known

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy office-2024 || rpm -q office-2024 || office-2024 --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

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-2026-70105?

microsoft 365: mitigate or apply the listed mitigation; office: downgrade or apply the listed mitigation; office 2021: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-70105 being exploited?

CVE-2026-70105 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-2026-70105 affect?

CVE-2026-70105 affects microsoft 365, office, office 2021. Severity is medium (CVSS 6.5). Improper input validation in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.

How urgent is CVE-2026-70105?

Priority 43/100. On your watchlist

Software pages

Microsoft Office vulnerabilities

Related CVEs

CVE-2026-68813 MEDIUM 5.5 MITIGATE MITIGATE Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information locally.
CVE-2026-70310 MEDIUM 5.5 MITIGATE MITIGATE Out-of-bounds read in Microsoft Office Word allows an unauthorized attacker to disclose information locally.
CVE-2026-68800 HIGH 7.8 MITIGATE DOWNGRADE Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
CVE-2026-68798 HIGH 7.8 MITIGATE MITIGATE Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
CVE-2026-108430 HIGH 8.8 MITIGATE MITIGATE Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a net

References

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