diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8a160f70b..f81daf070 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## Unreleased
+
+### Dependencies
+
+- Bump `proguard` from v5.5.0 to v5.6.1
+  This also bumps the proguard cache version from v3 to v4. ([#1734](https://github.com/getsentry/symbolicator/pull/1734))
+
 ## 25.7.0
 
 ### Various fixes & improvements
diff --git a/Cargo.lock b/Cargo.lock
index ac0d9a050..913fd59b1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3683,10 +3683,12 @@ dependencies = [
 
 [[package]]
 name = "proguard"
-version = "5.5.0"
+version = "5.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bafe48b490e1b00c4b69f24f9ec2957dd850930460515802f5a7399e015f18ed"
+checksum = "3a199b2f766cfc8f351e1dfcb9974ed0e27f6d22bdbf000230c90e1da6200b39"
 dependencies = [
+ "serde",
+ "serde_json",
  "thiserror 1.0.61",
  "watto",
 ]
@@ -4474,9 +4476,9 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.204"
+version = "1.0.219"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bc76f558e0cbb2a839d37354c575f1dc3fdc6546b5be373ba43d95f231bf7c12"
+checksum = "5f0e2c6ed6606019b4e29e69dbaba95b11854410e5347d525002456dbbb786b6"
 dependencies = [
  "serde_derive",
 ]
@@ -4492,9 +4494,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.204"
+version = "1.0.219"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0cd7e117be63d3c3678776753929474f3b04a43a080c744d6b0ae2a8c28e222"
+checksum = "5b0276cf7f2c73365f7157c8123c21cd9a50fbbd844757af28ca1f5925fc2a00"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4503,11 +4505,12 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.120"
+version = "1.0.140"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4e0d21c9a8cae1235ad58a00c11cb40d4b1e5c784f1ef2c537876ed6ffd8b7c5"
+checksum = "20068b6e96dc6c9bd23e01df8827e6c7e1f2fddd43c21810382803c136b99373"
 dependencies = [
  "itoa",
+ "memchr",
  "ryu",
  "serde",
 ]
@@ -5265,6 +5268,7 @@ dependencies = [
  "jsonwebtoken",
  "moka",
  "once_cell",
+ "proguard",
  "rand 0.8.5",
  "rayon",
  "reqwest",
diff --git a/Cargo.toml b/Cargo.toml
index 1e3c05d60..38d9a802d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -55,6 +55,7 @@ cpp_demangle = { git = "https://github.com/getsentry/cpp_demangle", branch = "se
 
 
 [workspace.dependencies]
+proguard = "5.6.1"
 reqwest = "0.12.15"
 serde-vars = "0.2.0"
 symbolic = "12.15.5"
diff --git a/crates/symbolicator-proguard/Cargo.toml b/crates/symbolicator-proguard/Cargo.toml
index b166c0b9f..ddc0b0dd2 100644
--- a/crates/symbolicator-proguard/Cargo.toml
+++ b/crates/symbolicator-proguard/Cargo.toml
@@ -8,7 +8,7 @@ license = "MIT"
 
 [dependencies]
 futures = "0.3.12"
-proguard = "5.5.0"
+proguard = { workspace = true }
 serde = { version = "1.0.137", features = ["derive", "rc"] }
 serde_json = "1.0.81"
 symbolic = { workspace = true }
diff --git a/crates/symbolicator-proguard/tests/integration/snapshots/integration__proguard__source_lookup_with_proguard.snap b/crates/symbolicator-proguard/tests/integration/snapshots/integration__proguard__source_lookup_with_proguard.snap
index 69855ef06..fe3a27bfc 100644
--- a/crates/symbolicator-proguard/tests/integration/snapshots/integration__proguard__source_lookup_with_proguard.snap
+++ b/crates/symbolicator-proguard/tests/integration/snapshots/integration__proguard__source_lookup_with_proguard.snap
@@ -97,9 +97,8 @@ stacktraces:
         lineno: 7
         index: 17
       - function: onMenuItemClick
-        filename: EditActivity
+        filename: R8$$SyntheticClass
         module: io.sentry.samples.instrumentation.ui.EditActivity$$InternalSyntheticLambda$1$ebaa538726b99bb77e0f5e7c86443911af17d6e5be2b8771952ae0caa4ff2ac7$0
-        abs_path: EditActivity
         lineno: 0
         in_app: true
         index: 18
diff --git a/crates/symbolicator-service/Cargo.toml b/crates/symbolicator-service/Cargo.toml
index be8d8d464..a23b8ee9c 100644
--- a/crates/symbolicator-service/Cargo.toml
+++ b/crates/symbolicator-service/Cargo.toml
@@ -30,6 +30,7 @@ ipnetwork = "0.20.0"
 jsonwebtoken = "9.1.0"
 moka = { version = "0.12.8", features = ["future", "sync"] }
 once_cell = "1.17.1"
+proguard = { workspace = true }
 rand = "0.8.5"
 rayon = "1.10.0"
 reqwest = { workspace = true, features = [
diff --git a/crates/symbolicator-service/src/caches/versions.rs b/crates/symbolicator-service/src/caches/versions.rs
index ff778b330..fe768d5f6 100644
--- a/crates/symbolicator-service/src/caches/versions.rs
+++ b/crates/symbolicator-service/src/caches/versions.rs
@@ -265,19 +265,24 @@ pub const BUNDLE_INDEX_CACHE_VERSIONS: CacheVersions = CacheVersions {
 
 /// Proguard Cache, with the following versions:
 ///
+/// - `4`: Information about classes/methods being synthesized is now part
+///   of the cache format.
+///
 /// - `3`: Restructuring the cache directory format.
 ///
 /// - `2`: Use proguard cache format (<https://github.com/getsentry/symbolicator/pull/1491>).
 ///
 /// - `1`: Initial version.
 pub const PROGUARD_CACHE_VERSIONS: CacheVersions = CacheVersions {
-    current: CacheVersion::new(3, CachePathFormat::V2),
-    fallbacks: &[CacheVersion::new(2, CachePathFormat::V1)],
+    current: CacheVersion::new(4, CachePathFormat::V2),
+    fallbacks: &[],
     previous: &[
         CacheVersion::new(1, CachePathFormat::V1),
         CacheVersion::new(2, CachePathFormat::V1),
+        CacheVersion::new(3, CachePathFormat::V2),
     ],
 };
+static_assert!(proguard::PRGCACHE_VERSION == 2);
 
 /// Symstore index cache, with the following versions:
 ///