The forum is offering bounties for security vulnerabilities.

The bounty amount is the highest applicable base bounty multiplied by all applicable modifiers. Amounts are in troy ounces of gold (converted to BTC at the time of payment).

Base bounties

	Root access	Arbitrary DB writing	Obtaining arbitrary PMs or password hashes	Persistent script injection	CSRF or non-persistent XSS
Admin attacker	8	2	1	0.1	0.1
User with manually-granted extra permissions (mod, etc.)	10	7	6	0.25	0.1
Regular user	10	8	7	0.5	0.1

Modifiers

Affects dev installation (including beta.bitcointalk.org) only	25%, capped at 1 XAU total
Stopped by SELinux, file permissions, etc. in practice	10%
Affected functionality currently disabled, but planned to be enabled	75%
Problem in the forum's production custom PHP code	110%
Security flaw in non-PHP software used by the forum (nginx, Linux, etc.)	150%
Someone has already published the flaw in a news article, blog, public forum, etc. with a reasonably high level of detail and specificity	50% - 25%, depending on how recently the article was published
Your testing of the vulnerability caused substantial disruptions	25%
No proof of concept	50%

Rules
- You must disclose the vulnerability only to me. Do not test your vulnerability in such a way that it would give others any information about the vulnerability.
- I must not already know about the vulnerability.
- Your info must actually convince me to make changes. If you give me info that is insufficient to convince me to change things, and then a few months later I get more info from someone else which does convince me to fix the thing that you reported, then you'll likely not be awarded a bounty.
- You must not use your exploit in any malicious way, or use it to read any database info that isn't public except for accounts that you control.
- It must be fairly easy for me to check the validity of your vulnerability. You must have proof of concept code, a live example of the exploit on the forum, or a very detailed description of the vulnerability. You can't just say something like, "Avatars can be used to execute PHP." That's not enough information, and it's very likely that the vulnerability you're talking about won't even affect the forum. Attacks using brute-force, timing, etc. that you can't demonstrate may not be eligible for bounties.
- DoS attacks aren't security vulnerabilities.
- Compromising an admin account is a valid technique, but you can't assume that you will be able to do this.
- Assume that CSRF attacks against the admin console don't work.
- If an exploit is only possible due to a combination of two or more flaws, then the bounty is calculated for each flaw assuming that it alone would succeed in the attack, and you get only the smallest of these bounties.
- You may receive a reward for reporting other security flaws (being able to delete posts when you shouldn't, for example), but these flaws are not covered by this bounty.
- I reserve the right to pay, not pay, or adjust bounties for any reason whatsoever, and to cancel/modify these rules without notice.

Extra bounties

These bounties use a separate system of calculation, but are subject to the same conditions as above.

- 1 XAU: Find the email address of user DefaultTrust and explain in detail how you did it.