Hello Jenkins Builder,

I'd like you to reexamine a change. Please visit

https://gerrit.osmocom.org/c/osmo-sgsn/+/43323?usp=email

to look at the new patch set (#2).

The following approvals got outdated and were removed: Verified+1 by Jenkins Builder

Change subject: ranap: reject oversized RANAP NAS-PDU ......................................................................

ranap: reject oversized RANAP NAS-PDU

The connection-oriented RANAP handlers ranap_handle_co_initial_ue() and ranap_handle_co_dt() copy the attacker-controlled NAS-PDU into a msgb allocated with a fixed 256 bytes. RANAP NAS-PDU is an unconstrained OCTET STRING, so the APER decoder accepts an arbitrarily large PDU; when nas_pdu.size exceeds the msgb tailroom, msgb_put() hits MSGB_ABORT and osmo_panic()s the process (MSGB_DEBUG is compiled in unconditionally), which a femtocell (HNB) peer can use to crash osmo-hnbgw / osmo-hnodeb by sending an InitialUE or DirectTransfer with a NAS-PDU > 256 bytes.

Validate nas_pdu.size against the msgb tailroom and drop the message gracefully instead of panicking.

This issue has been assigned the CVE candidate identifier CAN-2026-2051037.

This is a backport from osmo-iuh.git f06967126f486bcb185ccf3d1a8f9bc02c4da1f6

Change-Id: I2090c7acbf861dfc295a82ef32a976ea7742438b --- M src/sgsn/gprs_ranap.c 1 file changed, 14 insertions(+), 0 deletions(-)

git pull ssh://gerrit.osmocom.org:29418/osmo-sgsn refs/changes/23/43323/2