| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
dm-thin: fix metadata refcount underflow
There's a bug in dm-thin in the function rebalance_children. If the
internal btree node has one entry, the code tries to copy all btree
entries from the node's child to the node itself and then decrement the
child's reference count.
If the child node is shared (it has reference count > 1), we won't free
it, so there would be two pointers to each of the grandchildren nodes.
But the reference counts of the grandchildren is not increased, thus the
reference count doesn't match the number of pointers that point to the
grandchildren. This results in "device mapper: space map common: unable
to decrement block" errors.
Fix this bug by incrementing reference counts on the grandchildren if the
btree node is shared. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv
rxe_rcv() currently checks only that the incoming packet is at least
header_size(pkt) bytes long before payload_size() is used.
However, payload_size() subtracts both the attacker-controlled BTH pad
field and RXE_ICRC_SIZE from pkt->paylen:
payload_size = pkt->paylen - offset[RXE_PAYLOAD] - bth_pad(pkt)
- RXE_ICRC_SIZE
This means a short packet can still make payload_size() underflow even
if it includes enough bytes for the fixed headers. Simply requiring
header_size(pkt) + RXE_ICRC_SIZE is not sufficient either, because a
packet with a forged non-zero BTH pad can still leave payload_size()
negative and pass an underflowed value to later receive-path users.
Fix this by validating pkt->paylen against the full minimum length
required by payload_size(): header_size(pkt) + bth_pad(pkt) +
RXE_ICRC_SIZE. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix bc_ackers underflow on duplicate GRP_ACK_MSG
The GRP_ACK_MSG handler in tipc_group_proto_rcv() currently decrements
bc_ackers on every inbound group ACK, even when the same member has
already acknowledged the current broadcast round.
Because bc_ackers is a u16, a duplicate ACK received after the last
legitimate ACK wraps the counter to 65535. Once wrapped,
tipc_group_bc_cong() keeps reporting congestion and later group
broadcasts on the affected socket stay blocked until the group is
recreated.
Fix this by ignoring duplicate or stale ACKs before touching bc_acked or
bc_ackers. This makes repeated GRP_ACK_MSG handling idempotent and
prevents the underflow path. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gt: fix refcount underflow in intel_engine_park_heartbeat
A use-after-free / refcount underflow is possible when the heartbeat
worker and intel_engine_park_heartbeat() race to release the same
engine->heartbeat.systole request.
The heartbeat worker reads engine->heartbeat.systole and calls
i915_request_put() on it when the request is complete, but clears
the pointer in a separate, non-atomic step. Concurrently, a request
retirement on another CPU can drop the engine wakeref to zero, triggering
__engine_park() -> intel_engine_park_heartbeat(). If the heartbeat
timer is pending at that point, cancel_delayed_work() returns true and
intel_engine_park_heartbeat() reads the stale non-NULL systole pointer
and calls i915_request_put() on it again, causing a refcount underflow:
```
<4> [487.221889] Workqueue: i915-unordered engine_retire [i915]
<4> [487.222640] RIP: 0010:refcount_warn_saturate+0x68/0xb0
...
<4> [487.222707] Call Trace:
<4> [487.222711] <TASK>
<4> [487.222716] intel_engine_park_heartbeat.part.0+0x6f/0x80 [i915]
<4> [487.223115] intel_engine_park_heartbeat+0x25/0x40 [i915]
<4> [487.223566] __engine_park+0xb9/0x650 [i915]
<4> [487.223973] ____intel_wakeref_put_last+0x2e/0xb0 [i915]
<4> [487.224408] __intel_wakeref_put_last+0x72/0x90 [i915]
<4> [487.224797] intel_context_exit_engine+0x7c/0x80 [i915]
<4> [487.225238] intel_context_exit+0xf1/0x1b0 [i915]
<4> [487.225695] i915_request_retire.part.0+0x1b9/0x530 [i915]
<4> [487.226178] i915_request_retire+0x1c/0x40 [i915]
<4> [487.226625] engine_retire+0x122/0x180 [i915]
<4> [487.227037] process_one_work+0x239/0x760
<4> [487.227060] worker_thread+0x200/0x3f0
<4> [487.227068] ? __pfx_worker_thread+0x10/0x10
<4> [487.227075] kthread+0x10d/0x150
<4> [487.227083] ? __pfx_kthread+0x10/0x10
<4> [487.227092] ret_from_fork+0x3d4/0x480
<4> [487.227099] ? __pfx_kthread+0x10/0x10
<4> [487.227107] ret_from_fork_asm+0x1a/0x30
<4> [487.227141] </TASK>
```
Fix this by replacing the non-atomic pointer read + separate clear with
xchg() in both racing paths. xchg() is a single indivisible hardware
instruction that atomically reads the old pointer and writes NULL. This
guarantees only one of the two concurrent callers obtains the non-NULL
pointer and performs the put, the other gets NULL and skips it.
(cherry picked from commit 13238dc0ee4f9ab8dafa2cca7295736191ae2f42) |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: fix potential underflow in virtio_transport_get_credit()
The credit calculation in virtio_transport_get_credit() uses unsigned
arithmetic:
ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
If the peer shrinks its advertised buffer (peer_buf_alloc) while bytes
are in flight, the subtraction can underflow and produce a large
positive value, potentially allowing more data to be queued than the
peer can handle.
Reuse virtio_transport_has_space() which already handles this case and
add a comment to make it clear why we are doing that.
[Stefano: use virtio_transport_has_space() instead of duplicating the code]
[Stefano: tweak the commit message] |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix overflow of jump offset in constant blinding
bpf_jit_blind_insn() rewrites 'if rX op imm goto off' into:
AX = imm ^ rnd
AX ^= rnd
if rX op AX goto off
and subtracts 2 from off when the jump is backward. off is s16, so
-32767 and -32768 wrap and the jump goes 32767 insns forward, past the
end of the prog. The jump is inside the patch, hence bpf_adj_branches()
doesn't check it. The kernel crashes when such prog runs with
bpf_jit_harden=2.
Return -ERANGE in such case. bpf_jit_blind_constants() fails the same
way when blinding of other insns moves a jump out of range. |
| smpeg through 2.0.0 contains an integer underflow vulnerability in stream_header() in MPEGsystem.cpp that allows attackers to wrap packet_size by declaring an undersized packet length. Attackers can supply a crafted MPEG file opened via SMPEG_new, SMPEG_new_rwops or SMPEG_new_data to trigger a reachable assertion or out-of-bounds copy, crashing the application. |
| Integer underflow (wrap or wraparound) in DNS Server allows an unauthorized attacker to execute code over a network. |
| An integer underflow in OpenVPN version 2.7_alpha3 through 2.7.7 on Windows and Android allows remote authenticated servers to cause a denial of service or memory disclosure via crafted domain search options |
| FreeRDP before 3.32.0 contains a divide-by-zero vulnerability in the freerdp-shadow-cli shadow server: the frame id in a client's Frame Acknowledge PDU is stored without a range check, so the in-flight frame count in shadow_encoder_inflight_frames() can underflow. An authenticated client can acknowledge a frame id one greater than the last frame sent, causing shadow_encoder_create_frame_id() to divide by zero (SIGFPE) and terminate the process, disconnecting all viewers. |
| Integer underflow (wrap or wraparound) in Windows PowerShell allows an unauthorized attacker to execute code over a network. |
| Integer underflow (wrap or wraparound) in Windows Installer allows an authorized attacker to elevate privileges locally. |
| The receive path of the NXP KW41Z IEEE 802.15.4 driver, kw41z_rx() in drivers/ieee802154/ieee802154_kw41z.c, computed the payload size as pkt_len = len - KW41Z_FCS_LENGTH in a uint8_t, where len is the frame length reported by the radio. The interrupt handler kw41z_isr() obtained that length from the RX_FRAME_LENGTH field of the ZLL IRQSTS register — a copy of the PHY header length byte of the frame received over the air — and only rejected the value zero. A reported length of one therefore underflowed to pkt_len == 255.
Because the packet is allocated with NET_AF_UNSPEC on a non-Ethernet L2, net_pkt_rx_alloc_with_buffer() does not clamp the request to the interface MTU; with the default fixed-size buffer pool (CONFIG_NET_BUF_FIXED_DATA_SIZE, CONFIG_NET_BUF_DATA_SIZE=128) the allocation succeeded as a chain of two fragments. The subsequent register-to-buffer copy loops write into the first fragment only, so 255 bytes were written into a 128-byte net_buf data block, overrunning it by up to 127 bytes into adjacent network-buffer-pool memory, and reading up to 128 bytes past the end of the radio's PKT_BUFFER_RX register array.
The length field originates from an unauthenticated frame transmitted by any device within 802.15.4 radio range, and is captured by the hardware at PHY-header time — before frame filtering has completed — while the handler samples it after clearing the interrupt status, so an attacker flooding frames with a length byte of one can drive the underflow. The impact is memory corruption in the shared receive buffer pool from interrupt context, most plausibly a crash or corruption of other packets' data; the overflowing bytes are radio register contents rather than attacker-authored data, which bounds the integrity impact.
The fix rejects any length below KW41Z_FCS_LENGTH and additionally verifies net_buf_tailroom() of the first fragment before the copy loops, which also covers the CONFIG_NET_L2_OPENTHREAD variant of the size computation. |
| Integer underflow (wrap or wraparound) in Windows Kerberos allows an authorized attacker to elevate privileges locally. |
| ExtUtils::Typemaps::STL::Vector versions before 1.05 for Perl allocate a 32 GiB array on an empty list.
The OUTPUT typemaps call av_extend( av, len-1 ). On an empty list, this undeflows, and av_extend will allocate an array with 2^32 slots, leading to memory exhaustion. |
| Integer underflow (wrap or wraparound) in Microsoft Bluetooth Driver allows an authorized attacker to elevate privileges over an adjacent network. |
| `_nx_secure_x509_parse_signature_data` computes the certificate signature's length as `tlv_length - 1` without first checking that `tlv_length` is non-zero. A certificate whose signature is an empty ASN.1 BIT STRING therefore parses successfully and leaves the certificate holding a signature length of `0xFFFFFFFF` and a signature pointer one byte past the end of the buffer. Certificates are parsed from the peer during the TLS handshake, so the input is remote and unauthenticated. |
| Remote Code Execution in Windows Routing and Remote Access Service (RRAS) allows attacker to gain an unauthorized access to victim's machine |
| Integer underflow (wrap or wraparound) in Windows NTFS allows an authorized attacker to disclose information locally. |
| An Integer Underflow vulnerability in the kernel of Juniper Networks Junos OS with Extended Echo configured allows an unauthenticated, network-based attacker to cause a denial of service by a kernel crash. |
