RDK B WebUI rdkb-2025q4-kirkstone Multipart Form-Data Parser jst_post.c memory corruption

Summaryinfo

A vulnerability marked as very critical has been reported in RDK B WebUI rdkb-2025q4-kirkstone. Affected by this vulnerability is an unknown functionality of the file jst_post.c of the component Multipart Form-Data Parser. Performing a manipulation results in memory corruption. This vulnerability is reported as CVE-2026-19508. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as very critical has been found in RDK B WebUI rdkb-2025q4-kirkstone. This affects an unknown code of the file jst_post.c of the component Multipart Form-Data Parser. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Heap-based buffer overflow in the multipart form-data parser in `jst_post.c` in RDK-B WebUI `rdkb-2025q4-kirkstone.04.10.26` allows a remote unauthenticated attacker to cause memory corruption and denial of service, and potentially execute arbitrary code, via a crafted multipart/form-data request.

It is possible to read the advisory at whitehats.pwr.edu.pl. This vulnerability is uniquely identified as CVE-2026-19508 since 08/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/19/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• RDK

Name

• B WebUI

Version

• rdkb-2025q4-kirkstone

CPE 2.3info

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CPE 2.2info

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Entryinfo

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