CVE-2025-29635
CVE-2025-29635 is a security flaw in D-Link DIR-823X, routers for homes and small offices. Attackers can run commands on D-Link DIR-823X. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 24 Apr 2026.[1]
D-Link DIR-823X is in things households have: home and small-office routers, so the fix matters at home as much as at work. D-Link has published a fix or advice.
Description
CISA calls it a command injection in D-Link DIR-823X. In its words: “D-Link DIR-823X contains a command injection vulnerability that allows an authorized attacker to execute arbitrary commands on remote devices by sending a POST request to /goform/set_prohibiting via the corresponding function. The impacted product could be end-of-life (EoL) and/or end-of-service (EoS). Users should discontinue product utilization.”[1]
The underlying weakness is command injection (CWE-77), in MITRE’s list of common software weaknesses.[2]
It scores 7.2 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by the organisation that published the CVE using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; D-Link’s advisory has them[3]. CISA names the product as D-Link DIR-823X.
Every device with D-Link DIR-823X needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 24 Apr 2026, 395 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 8 May 2026 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 88%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
D-Link has published a fix or advice.[3] CISA’s required action: “Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.”[1]
- Update D-Link DIR-823X now.Open the router’s app, or its admin page in a browser, and look for a firmware update. Then turn on automatic updates, so the next fix arrives on its own.
- If the maker has stopped updating it, replace it.Routers stop getting fixes after a few years, and attackers keep a list of the ones that did. If there’s no newer firmware, it won’t be fixed.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 7.2.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 88%.[4] |
See also
Other D-Link flaws
- CVE-2022-37055, D-Link Routers: buffer overflow ·
- CVE-2022-40799, D-Link DNR-322L: download of code without integrity check ·
- CVE-2020-25079, D-Link DCS-2530L and DCS-2670L Devices: DCS-2530L and DCS-2670L command injection ·
- CVE-2020-25078, D-Link DCS-2530L and DCS-2670L Devices: unspecified ·
- CVE-2024-0769, D-Link DIR-859 Router: path traversal ·
Other command injection flaws
- CVE-2026-105134, AhsayCBS: command injection ·
- CVE-2026-96951, Microsoft Windows: command injection ·
- CVE-2016-3081, Apache Struts: command injection ·
- CVE-2026-8037, Progress LoadMaster: command injection ·
- CVE-2026-22719, Broadcom VMware Aria Operations: command injection ·
Added the same day
- CVE-2024-7399, Samsung MagicINFO 9 Server: path traversal ·
- CVE-2024-57728, SimpleHelp: path traversal ·
- CVE-2024-57726, SimpleHelp: missing authorization ·
Every D-Link flaw on CISA’s list · Everything added in April 2026
References
- ^ Cybersecurity and Infrastructure Security Agency. “D-Link DIR-823X Command Injection Vulnerability”. Known Exploited Vulnerabilities Catalog, added 24 Apr 2026.
- ^ National Institute of Standards and Technology. “CVE-2025-29635 Detail”. National Vulnerability Database, published 25 Mar 2025.
- ^ D-Link. Advisories and fixes: supportannouncement.us.dlink.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.879, percentile 99.8, 31 Oct 2026.
- CVE Program. “CVE-2025-29635”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.