CVE-2021-21257
The RPL-Classic and RPL-Lite implementations in the Contiki-NG operating system versions prior to 4.6 do not validate the address pointer in the RPL source routing header This makes it possible for an attacker to cause out-of-bounds writes with packets…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.09%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Contiki-NG is an open-source, cross-platform operating system for internet of things devices. The RPL-Classic and RPL-Lite implementations in the Contiki-NG operating system versions prior to 4.6 do not validate the address pointer in the RPL source routing header This makes it possible for an attacker to cause out-of-bounds writes with packets injected into the network stack. Specifically, the problem lies in the rpl_ext_header_srh_update function in the two rpl-ext-header.c modules for RPL-Classic and RPL-Lite respectively. The addr_ptr variable is calculated using an unvalidated CMPR field value from the source routing header. An out-of-bounds write can be triggered on line 151 in os/net/routing/rpl-lite/rpl-ext-header.c and line 261 in os/net/routing/rpl-classic/rpl-ext-header.c, which contain the following memcpy call with addr_ptr as destination. The problem has been patched in Contiki-NG 4.6. Users can apply a patch out-of-band as a workaround.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.09% probability · 63th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- contiki-ng/contiki-ng
- Source
- security-advisories@github.com
References
- https://github.com/contiki-ng/contiki-ng/pull/1431Patch, Third Party Advisory
- https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-mvc7-9p4q-c5cmPatch, Third Party Advisory
- https://github.com/contiki-ng/contiki-ng/pull/1431Patch, Third Party Advisory
- https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-mvc7-9p4q-c5cmPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.