CVE-2021-41745: ShowDoc 2.8.3 ihas a file upload vulnerability, where attackers can use the vulnerability to obtain server per

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CRITICAL 9.8REMOTEDOWNGRADE

CVE-2021-41745 is a critical-severity flaw (CVSS 9.8) affecting showdoc. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

ShowDoc 2.8.3 ihas a file upload vulnerability, where attackers can use the vulnerability to obtain server permissions.

Why this priority

Critical severity
Remotely exploitable, no login, no user action

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

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.4% (top 28%)
CISA exploited list	No
Weakness	CWE-434
Published	2021-10-22
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: showdoc

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

Am I affected?

Timeline

2021-10-22 12:15 UTCPublished CVE record published
2026-06-17 04:08 UTCUpdated Record last modified

showdoc showdoc DOWNGRADE

Affected: 2.8.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.8.3

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 2.8.3 (Debian / Ubuntu)

apt-cache madison showdoc sudo apt install showdoc=<VERSION_BEFORE_2.8.3> sudo apt-mark hold showdoc

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

dnf --showduplicates list showdoc sudo dnf downgrade showdoc-<VERSION_BEFORE_2.8.3> sudo dnf versionlock add showdoc

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-2021-41745?

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

Is CVE-2021-41745 being exploited?

CVE-2021-41745 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-2021-41745 affect?

CVE-2021-41745 affects showdoc. Severity is critical (CVSS 9.8). ShowDoc 2.8.3 ihas a file upload vulnerability, where attackers can use the vulnerability to obtain server permissions.

How urgent is CVE-2021-41745?

Priority 57/100. Critical severity; Remotely exploitable, no login, no user action

Related CVEs

CVE-2022-1034 HIGH 7.2 UPGRADE There is a Unrestricted Upload of File vulnerability in ShowDoc v2.10.3 in GitHub repository star7th/showdoc p
CVE-2022-0967 MEDIUM 5.4 UPGRADE Stored XSS via File Upload in star7th/showdoc in star7th/showdoc in GitHub repository star7th/showdoc prior to
CVE-2022-0966 MEDIUM 5.4 UPGRADE Stored XSS via File Upload in star7th/showdoc in GitHub repository star7th/showdoc prior to 2.4.10.
CVE-2022-0965 MEDIUM 5.4 UPGRADE Stored XSS viva .ofd file upload in GitHub repository star7th/showdoc prior to 2.10.4.
CVE-2022-0964 MEDIUM 5.4 UPGRADE Stored XSS viva .webmv file upload in GitHub repository star7th/showdoc prior to 2.10.4.

References

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