CVE-2026-90011 is a vulnerability in Linux Kernel
Published on September 16, 2026
scsi: target: iscsi: Reserve a terminator byte for the login payload
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: iscsi: Reserve a terminator byte for the login payload
iscsi_target_check_login_request() rejects a login PDU whose
DataSegmentLength exceeds MAX_KEY_VALUE_PAIRS, but the test is '>' and
login->req_buf is allocated with exactly MAX_KEY_VALUE_PAIRS
bytes. Since iscsit_get_login_rx() receives payload_length + padding
bytes, where
padding = ((-payload_length) & 3);
any payload_length from 8189 to 8192 fills the whole 8192 byte
buffer. The write stays in bounds, but no byte is left for a NUL
terminator.
The buffer is subsequently consumed as a C string. In the CHAP path
chap_check_algorithm() calls kstrdup(a_str), and extract_param() calls
strstr(in_buf, pattern) followed by strlen_semi(), none of which take a
length. convert_null_to_semi() additionally rewrites every embedded NUL
to ';', so even a payload made of well formed NUL separated key=value
records is left without a terminator. These walk past the end of the
object into adjacent slab memory. It is reachable by an unauthenticated
initiator against a portal configured for CHAP; when authentication is
not required iscsi_login_zero_tsih_s2() rewrites AuthMethod to None and
the CHAP path is never entered.
Allocate one extra byte. kzalloc() zeroes it and nothing ever writes to
it, as every writer copies to offset 0 for at most MAX_KEY_VALUE_PAIRS
bytes, so the buffer is always terminated.
Products Associated with CVE-2026-90011
Want to know whenever a new CVE is published for Linux Kernel? stack.watch will email you.
Affected Versions
Linux:- Version e48354ce078c079996f89d715dfa44814b4eba01 and below 5fac79f248c37774d1dd761406f83d25ca6ff8e4 is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below 6ddddcad436d8e6e619204d3c848147ff2f5bf1e is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below b19dc17ed963ac36c0db4b52a1803fb11169f91f is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below 6b589ef9d5f6cdc70d2b4f269ca6cf26b5ebb076 is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below eb9dadf4d552ebe10644871c5189286552aa48f5 is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below 1624bff4c5118ad494d50ad94d44f22064667a7f is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below 3ddf3ea291a0ef2ea93b82e158960ac2cc42302b is affected.
- Version e48354ce078c079996f89d715dfa44814b4eba01 and below f4825922d2fb371e2b969697d792077f1b62b62c is affected.
- Version 3.1 is affected.
- Before 3.1 is unaffected.
- Version 5.10.270, <= 5.10.* is unaffected.
- Version 5.15.221, <= 5.15.* is unaffected.
- Version 6.1.188, <= 6.1.* is unaffected.
- Version 6.6.157, <= 6.6.* is unaffected.
- Version 6.12.110, <= 6.12.* is unaffected.
- Version 6.18.51, <= 6.18.* is unaffected.
- Version 7.2.5, <= 7.2.* is unaffected.
- Version 7.3-rc2, <= * is unaffected.