<p>CSV is not a stop-gap solution. Before you can say that, you first need to define what the problem is.</p>

<p>CSV solves the problem that you can't use CLTV in contracts that need a spending delay where the output itself will not be broadcast for an unknown amount of time. This is a very abstract problem, but it does occur as a primitive inside more complex constructions.</p>

<p>However, the current Thunder implementation uses a stop-gap solution to transaction malleability, which just happens to rely on CSV.</p>

CC BY-SA 3.0
2016-05-30T11:07:38.313Z
2016-05-30T11:07:38.313Z
Pieter Wuille
<p>The <a href="https://lightning.network/lightning-network-paper.pdf" rel="nofollow">Lightning Paper</a> v0.5.9.2 says that CSV "would permit further
abilities, including allowing a stop-gap solution before a more permanent
solution for resolving transaction malleability. A future version of this
paper will include proposed solutions."</p>

<p>This means that Thunder is still vulnerable to malleability attacks since it relies on CSV as a solution.</p>

<p>Since <a href="https://github.com/blockchain/thunder/blob/fc84b8de9378a9f5086c8fb6f198d2857766e167/README.md#feature-list" rel="nofollow">the Thunder readme</a> does not mention malleability fixes as a TODO point, I guess the Thunder authors considers it fixed. </p>

<p>The cited Lightning draft is from January.</p>

CC BY-SA 3.0
2016-05-30T08:33:17.510Z
Transaction Malleability is fixed by Segregated Witness.
Murch
<transaction-malleability><lightning-network><checksequenceverify>
Is CheckSequenceVerify only a stop-gap measure?
Janus Troelsen
# Is CheckSequenceVerify only a stop-gap measure?

(Asked by: username_0 on 2016-05-16)

The [Lightning Paper](https://lightning.network/lightning-network-paper.pdf) v0.5.9.2 says that CSV "would permit further
abilities, including allowing a stop-gap solution before a more permanent
solution for resolving transaction malleability. A future version of this
paper will include proposed solutions."

This means that Thunder is still vulnerable to malleability attacks since it relies on CSV as a solution.

Since [the Thunder readme](https://github.com/blockchain/thunder/blob/fc84b8de9378a9f5086c8fb6f198d2857766e167/README.md#feature-list) does not mention malleability fixes as a TODO point, I guess the Thunder authors considers it fixed.

The cited Lightning draft is from January.

**Tags:** transaction-malleability, lightning-network, checksequenceverify

> **Comments:**
> **username_1**: Transaction Malleability is fixed by Segregated Witness.  

---

## 1 answers

### Answer by username_2 on 2016-05-30. Score: 2 | Accepted answer

CSV is not a stop-gap solution. Before you can say that, you first need to define what the problem is.

CSV solves the problem that you can't use CLTV in contracts that need a spending delay where the output itself will not be broadcast for an unknown amount of time. This is a very abstract problem, but it does occur as a primitive inside more complex constructions.

However, the current Thunder implementation uses a stop-gap solution to transaction malleability, which just happens to rely on CSV.


---

