diff --git a/.github/workflows/security-scan.yml b/.github/workflows/security-scan.yml
index e13b093b..896f5c31 100644
--- a/.github/workflows/security-scan.yml
+++ b/.github/workflows/security-scan.yml
@@ -222,7 +222,9 @@ jobs:
       - name: Run cargo audit
         run: |
           cargo install cargo-audit --version 0.22.1 --locked
-          cd cli && cargo audit
+          # RUSTSEC-2026-0258: low-severity h2 DoS; direct h2 bumped to 0.4.18,
+          # remaining transitive h2 0.3.x via tonic 0.11 <- libsql has no patch (see deny.toml)
+          cd cli && cargo audit --ignore RUSTSEC-2026-0258
 
   # ============================================================================
   # RUST SECURITY (SAST, Deny, Outdated)
diff --git a/cli/Cargo.lock b/cli/Cargo.lock
index c893f106..ffd69731 100644
--- a/cli/Cargo.lock
+++ b/cli/Cargo.lock
@@ -91,7 +91,7 @@ version = "1.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "40c48f72fd53cd289104fc64099abca73db4166ad86ea0b4341abe65af83dadc"
 dependencies = [
- "windows-sys 0.61.2",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
@@ -102,7 +102,7 @@ checksum = "291e6a250ff86cd4a820112fb8898808a366d8f9f58ce16d1f538353ad55747d"
 dependencies = [
  "anstyle",
  "once_cell_polyfill",
- "windows-sys 0.61.2",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
@@ -761,7 +761,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "39cab71617ae0d63f51a36d69f866391735b51691dbda63cf6f96d042b63efeb"
 dependencies = [
  "libc",
- "windows-sys 0.61.2",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -992,9 +992,9 @@ dependencies = [
 
 [[package]]
 name = "h2"
-version = "0.4.14"
+version = "0.4.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "171fefbc92fe4a4de27e0698d6a5b392d6a0e333506bc49133760b3bcf948733"
+checksum = "839c0e8a181239723652be9062bb56ca5bf5f64011f73b623f6f4fc59086a228"
 dependencies = [
  "atomic-waker",
  "bytes",
@@ -1191,7 +1191,7 @@ dependencies = [
  "bytes",
  "futures-channel",
  "futures-core",
- "h2 0.4.14",
+ "h2 0.4.18",
  "http 1.4.0",
  "http-body 1.0.1",
  "httparse",
@@ -1247,7 +1247,7 @@ dependencies = [
  "libc",
  "percent-encoding",
  "pin-project-lite",
- "socket2 0.6.3",
+ "socket2 0.5.10",
  "tokio",
  "tower-service",
  "tracing",
@@ -1769,7 +1769,7 @@ version = "0.50.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7957b9740744892f114936ab4a57b3f487491bbeafaf8083688b16841a4240e5"
 dependencies = [
- "windows-sys 0.61.2",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -2026,7 +2026,7 @@ dependencies = [
  "quinn-udp",
  "rustc-hash 2.1.2",
  "rustls",
- "socket2 0.6.3",
+ "socket2 0.5.10",
  "thiserror 2.0.20",
  "tokio",
  "tracing",
@@ -2063,7 +2063,7 @@ dependencies = [
  "cfg_aliases",
  "libc",
  "once_cell",
- "socket2 0.6.3",
+ "socket2 0.5.10",
  "tracing",
  "windows-sys 0.60.2",
 ]
@@ -2242,7 +2242,7 @@ dependencies = [
  "base64 0.22.1",
  "bytes",
  "futures-core",
- "h2 0.4.14",
+ "h2 0.4.18",
  "http 1.4.0",
  "http-body 1.0.1",
  "http-body-util",
@@ -2321,7 +2321,7 @@ dependencies = [
  "errno",
  "libc",
  "linux-raw-sys 0.12.1",
- "windows-sys 0.61.2",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -2527,7 +2527,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3a766e1110788c36f4fa1c2b71b387a7815aa65f88ce0229841826633d93723e"
 dependencies = [
  "libc",
- "windows-sys 0.61.2",
+ "windows-sys 0.60.2",
 ]
 
 [[package]]
@@ -2606,7 +2606,7 @@ dependencies = [
  "getrandom 0.4.2",
  "once_cell",
  "rustix 1.1.4",
- "windows-sys 0.61.2",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -3276,7 +3276,7 @@ version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c2a7b1c03c876122aa43f3020e6c3c3ee5c05081c9a00739faf7503aeba10d22"
 dependencies = [
- "windows-sys 0.61.2",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
diff --git a/deny.toml b/deny.toml
index 127af790..92210d97 100644
--- a/deny.toml
+++ b/deny.toml
@@ -9,6 +9,11 @@ db-urls = ["https://github.com/rustsec/advisory-db"]
 # Any advisory ids to ignore e.g. ["RUSTSEC-2019-0001", "...]
 ignore = [
     "RUSTSEC-2025-0141", # bincode is unmaintained
+    # h2 unbounded empty DATA frames (low, DoS). Patched only in >=0.4.16; the
+    # remaining hit is the transitive h2 0.3.x via tonic 0.11 <- libsql, which has
+    # no patched 0.3 release. Upgrading requires a tonic/libsql major bump
+    # (tracked separately); CLI exposure is client-side sync, not an h2 server.
+    "RUSTSEC-2026-0258",
 ]
 
 # Options for checking licenses