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Medium

Authenticated local CLI buffer overflow DoS in Cisco IOS and IOS XE

IdentifiersCVE-2025-20149CWE-120· Buffer Copy without Checking Size…

CVE-2025-20149 is a buffer overflow vulnerability in the command-line interface (CLI) of Cisco IOS Software and Cisco IOS XE Software. According to the provided content, an authenticated local attacker with a low-privileged account can trigger the flaw by entering crafted commands at the CLI prompt. Successful exploitation causes the affected device to reload unexpectedly, producing a denial-of-service condition. The available information identifies the issue as a CLI-side buffer overflow but does not provide the specific vulnerable function or code path.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation causes an affected Cisco IOS or IOS XE device to reload unexpectedly, interrupting device availability and resulting in a denial-of-service condition. The impact described in the provided content is service disruption rather than code execution or privilege escalation.

Mitigation

If you can’t patch tonight, do this now.

No specific mitigation for CVE-2025-20149 is provided in the supplied content beyond applying Cisco’s fixes. As an exposure-reduction measure, organizations can limit local CLI access to trusted administrators, minimize the number of low-privileged local accounts, and enforce strong access controls for management access, but the authoritative remediation in the provided material is to patch affected systems.

Remediation

Patch, then assume compromise.

Apply the Cisco software updates that address CVE-2025-20149 in affected Cisco IOS Software and Cisco IOS XE Software releases. The provided content indicates that Cisco included a patch for this vulnerability in its security updates and recommends updating vulnerable products in accordance with Cisco’s version-specific guidance and advisories.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

6 SOURCESView more in app
What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
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Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity3

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2025-20149
NVD
nvd.nist.gov/vuln/detail/CVE-2025-20149
MITRE CWE · CWE-120
Buffer Copy without Checking Size of Input…
sec.cloudapps.cisco.com
sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-cli-EB7cZ6yO