diff --git a/CHANGELOG.md b/CHANGELOG.md
index f84b2b3..bd612a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Prefix decoding is now more resilient to bad prefix lenghts.
+
 ## [0.3.0] - 2024-01-17
 
 ### Added
diff --git a/src/babel/route_request.rs b/src/babel/route_request.rs
index 91ff515..e89ebaa 100644
--- a/src/babel/route_request.rs
+++ b/src/babel/route_request.rs
@@ -56,18 +56,27 @@ impl RouteRequest {
         let prefix_ip = match ae {
             AE_WILDCARD => None,
             AE_IPV4 => {
+                if plen > 32 {
+                    return None;
+                }
                 let mut raw_ip = [0; 4];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Some(Ipv4Addr::from(raw_ip).into())
             }
             AE_IPV6 => {
+                if plen > 128 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Some(Ipv6Addr::from(raw_ip).into())
             }
             AE_IPV6_LL => {
+                if plen != 64 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[0] = 0xfe;
                 raw_ip[1] = 0x80;
diff --git a/src/babel/seqno_request.rs b/src/babel/seqno_request.rs
index 4160a86..3446cc5 100644
--- a/src/babel/seqno_request.rs
+++ b/src/babel/seqno_request.rs
@@ -105,22 +105,34 @@ impl SeqNoRequest {
 
         let prefix = match ae {
             AE_WILDCARD => {
+                if plen != 0 {
+                    return None;
+                }
                 // TODO: this is a temporary placeholder until we figure out how to handle this
                 Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0).into()
             }
             AE_IPV4 => {
+                if plen > 32 {
+                    return None;
+                }
                 let mut raw_ip = [0; 4];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Ipv4Addr::from(raw_ip).into()
             }
             AE_IPV6 => {
+                if plen > 128 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Ipv6Addr::from(raw_ip).into()
             }
             AE_IPV6_LL => {
+                if plen != 64 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[0] = 0xfe;
                 raw_ip[1] = 0x80;
@@ -257,7 +269,7 @@ mod tests {
 
         let mut buf = bytes::BytesMut::from(
             &[
-                3, 92, 0, 42, 232, 0, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+                3, 64, 0, 42, 232, 0, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
                 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0, 10, 0, 20, 0, 30, 0,
                 40,
             ][..],
@@ -266,7 +278,7 @@ mod tests {
         let snr = super::SeqNoRequest {
             seqno: 42.into(),
             hop_count: NonZeroU8::new(232).unwrap(),
-            prefix: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 92)
+            prefix: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 64)
                 .expect("92 is a valid IPv6 prefix size; qed"),
             router_id: RouterId::from([4u8; RouterId::BYTE_SIZE]),
         };
diff --git a/src/babel/update.rs b/src/babel/update.rs
index 8ab94a3..4256c11 100644
--- a/src/babel/update.rs
+++ b/src/babel/update.rs
@@ -104,22 +104,34 @@ impl Update {
         let prefix_size = ((plen + 7) / 8) as usize;
         let prefix = match ae {
             AE_WILDCARD => {
+                if prefix_size != 0 {
+                    return None;
+                }
                 // TODO: this is a temporary placeholder until we figure out how to handle this
                 Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0).into()
             }
             AE_IPV4 => {
+                if plen > 32 {
+                    return None;
+                }
                 let mut raw_ip = [0; 4];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Ipv4Addr::from(raw_ip).into()
             }
             AE_IPV6 => {
+                if plen > 128 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[..prefix_size].copy_from_slice(&src[..prefix_size]);
                 src.advance(prefix_size);
                 Ipv6Addr::from(raw_ip).into()
             }
             AE_IPV6_LL => {
+                if plen != 64 {
+                    return None;
+                }
                 let mut raw_ip = [0; 16];
                 raw_ip[0] = 0xfe;
                 raw_ip[1] = 0x80;
@@ -262,7 +274,7 @@ mod tests {
 
         let mut buf = bytes::BytesMut::from(
             &[
-                3, 0, 92, 0, 3, 232, 0, 42, 3, 1, 0, 10, 0, 20, 0, 30, 0, 40, 4, 4, 4, 4, 4, 4, 4,
+                3, 0, 64, 0, 3, 232, 0, 42, 3, 1, 0, 10, 0, 20, 0, 30, 0, 40, 4, 4, 4, 4, 4, 4, 4,
                 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
                 4, 4, 4, 4, 4,
             ][..],
@@ -273,7 +285,7 @@ mod tests {
             interval: 1000,
             seqno: 42.into(),
             metric: 769.into(),
-            subnet: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 92)
+            subnet: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 64)
                 .expect("92 is a valid IPv6 prefix size; qed"),
             router_id: RouterId::from([4u8; RouterId::BYTE_SIZE]),
         };
@@ -311,7 +323,7 @@ mod tests {
         // Set all flag bits, only allowed bits should be set on the decoded value
         let mut buf = bytes::BytesMut::from(
             &[
-                3, 255, 92, 0, 3, 232, 0, 42, 3, 1, 0, 10, 0, 20, 0, 30, 0, 40, 4, 4, 4, 4, 4, 4,
+                3, 255, 64, 0, 3, 232, 0, 42, 3, 1, 0, 10, 0, 20, 0, 30, 0, 40, 4, 4, 4, 4, 4, 4,
                 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
                 4, 4, 4, 4, 4, 4,
             ][..],
@@ -322,7 +334,7 @@ mod tests {
             interval: 1000,
             seqno: 42.into(),
             metric: 769.into(),
-            subnet: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 92)
+            subnet: Subnet::new(Ipv6Addr::new(0xfe80, 0, 0, 0, 10, 20, 30, 40).into(), 64)
                 .expect("92 is a valid IPv6 prefix size; qed"),
             router_id: RouterId::from([4u8; RouterId::BYTE_SIZE]),
         };