The Stack — November 06, 2026

Daily IT Briefing: Nov 6, 2026

Today's theme is the edge case nobody tested. An error string happened to match a "no password" marker and opened SSH on Alpine. AI agents formalizing a 7,500-page math reference turned up dozens of statements with missing hypotheses. Agility goes public with $174K in half-year revenue against a $362M loss, so its valuation rests on a robot that hasn't been shown publicly.

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Cybersecurity Alpine Linux: OpenSSH password bypass with a single connection

This is the most urgent item today. An attacker who can reach the SSH port can log in to affected accounts without knowing a password, on the first try. No CVE had been assigned at disclosure.

How it works. The bug comes from an interaction between OpenSSH's non-PAM password path and musl's `crypt()`:

1. For an account with password field `*` (no password set), sshd borrows the salt from another account's `$5$`/`$6$` hash.

2. The attacker sends a password of 257–1024 bytes.

3. When a key exceeds 256 bytes, musl's `crypt()` returns `*` to signal an error.

4. That `*` matches the stored field, so the login succeeds.

You're exposed if all of these are true:

• You run the non-PAM `openssh-server`, or `openssh-server-pam` with `UsePAM no`.
• `PasswordAuthentication yes` is set. This is the OpenSSH default.
• At least one account has a `*` password field.
• At least one other local account has a SHA-256 or SHA-512 crypt hash.

Accounts at risk:

• Key-only users.
• Directory users served through musl-nscd.
• `root`, directly only with `PermitRootLogin yes`. It is also reachable indirectly through any account with `doas` rights.
• Official tiny-cloud images, releases 3.18.11–3.24.3. These ship an `alpine` user with `*` and passwordless `doas`. They become exploitable as soon as any `$6$` hash exists, for example after someone sets a console password.

Not affected:

• Containers that don't run sshd.
• Systems with `PasswordAuthentication no`.
• PAM builds with `UsePAM yes`.
• Locked (`!`) accounts.
• Cloud-init-configured images, because cloud-init disables password authentication.

Affected versions: every release checked, from 3.16 through 3.24 plus edge.

What to do

• Upgrade to 3.21.10, 3.22.8, 3.23.8 or 3.24.4. Fixes were also backported to unsupported branches down to 3.16. The upstream fix is in OpenSSH 10.6p2.
• Restart sshd after upgrading. The running daemon is not replaced automatically.
• Interim workaround: set `PasswordAuthentication no`, then restart sshd.
• Hunt for signs of compromise:
• Search `/var/log/messages` for `Accepted password for` on accounts that have no password.
• Audit `doas` usage, new users and changes to `authorized_keys`.
• If you can't rule out a login, treat the host as compromised.

Takeaway: Error sentinels that share a value with valid data are a classic source of authentication bugs. Any comparison against a value like `*` deserves a second look in code review.

iOS and Android zero-days used against diplomats

Researchers report that attackers exploited vulnerabilities in both iOS and Android to infect phones in what appears to be a campaign aimed at diplomats. The researchers suggest the operator may be Kremlin-sponsored. That is a possibility they raise, not a confirmed attribution. Specific CVEs, patch status and the infection vector have not been reported yet. High-risk users should apply pending OS updates and consider lockdown-style modes until more details come out.

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AI/ML Axiom formalizes the entire Stacks Project in Lean

Axiom Math, a startup valued at $1.6B, says AI agents produced a Lean formalization of the full Stacks Project. The Stacks Project is the open-source algebraic geometry reference Johan de Jong started in 2005. The result is roughly 16 million lines of proof-checked code. Reported page counts vary slightly, between about 7,500 and 7,654.

Why it matters. Algebraic geometry has been a major gap in Mathlib-style formal libraries. A machine-checked base would let researchers verify new work against established results. Axiom calls it the largest integrated, reusable formal math library ever built. That is the company's claim and has not been verified independently.

How it was built. Accounts differ on how structured the process was:

• One description: hierarchical "swarms" of coordinated agents translated statements, searched Mathlib for existing abstractions, proved theorems, and kept definitions and typeclass interfaces consistent across chapters.
• Another description: a looser hierarchy in which agents largely picked their own tasks.

Both accounts agree on two points. The work relied on Axiom's in-house math-trained models, and it built on years of Lean and Mathlib community groundwork.

Fidelity checks. A proof assistant confirms that each proof is valid. It does not confirm that each formal statement means what the original text says. Axiom cites four checks for that gap:

• multi-agent auditing,
• semantic cross-checks against the source text,
• the requirement that every result plug into the downstream theorems that depend on it,
• targeted audits of key definitions and landmark theorems.

No independent assessment of completeness or fidelity has been published. That review is the real test.

Errors found in the source. Axiom says the process surfaced dozens of statements that needed refinement, including:

• missing hypotheses,
• edge cases in positive characteristic,
• overgeneralized claims.

Its agents produced counterexamples and corrected statements, or found alternative proofs where deeper theorems were affected.

Navigation. The library keeps Stacks' permanent tags and offers a side-by-side view of the original text and Lean code, plus an interactive dependency graph.

Governance. de Jong recently asked that no AI-generated comments or pull requests be sent to the upstream Stacks repository. Axiom keeps its formalization and fixes in its own open-source repository, so the corrections won't automatically reach the canonical text.

Context. This follows Axiom's formalization of the Classification of Finite Simple Groups in October. CEO Carina Hong is pitching verified libraries as groundwork for agents that write bug-free software. She also challenged coding-AI companies to attempt formalization at this scale.

Policy: the industry reads anti-AI votes as anti-Trump votes

Recent votes to restrict AI and data center development have prompted a split in interpretation:

• Major tech companies argue the votes reflect opposition to the Trump administration rather than to the technology.
• Critics describe the industry as "in denial" and say voters backed restrictions "overwhelmingly."

The jurisdictions, margins and scope of the measures haven't been detailed, so it isn't yet possible to judge how broad the backlash is. Watch for local zoning and power-grid fights over data center siting as the concrete version of this debate.

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Semiconductors AMD posts a record $13.4B quarter

• Data center revenue roughly doubled and drove the record result.
• Gaming revenue fell about 40%.

AMD's growth now depends heavily on AI accelerators and EPYC server demand. That makes the company more exposed to hyperscaler capex cycles and less to consumer demand.

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Industry Dropbox buys Tigris Data for $350M and launches DBX Agent Cloud

The deal is reportedly Dropbox's largest acquisition to date and is expected to close in Q4 2026.

Tigris. Founded by former Uber storage engineers, Tigris builds object storage that automatically places data near the users and compute that access it. It raised a $25M Series A last year.

DBX Agent Cloud is a new storage platform for teams building AI models and agents:

• At launch: standalone S3-compatible object storage.
• Planned: multimodal content handling (documents, images, audio, video) and filesystem semantics that let agents keep state across tasks and sessions.

Core Dropbox changes:

• Users can run AI tasks on their files and choose which model to use.
• Files can connect to ChatGPT, Claude, Muse and other third-party tools.
• The rollout covers eligible Standard and Advanced customers in the US, UK and Australia. Dropbox says 70,000+ teams have it, with broader availability planned for 2027.

Workforce: Dropbox says the deal brings no layoffs. It cut about 9% of staff last month.

Analysis: This positions Dropbox against S3, R2 and similar services in agent storage. Its advantage is a large installed base of existing customer files.

Zipline raises $1.5B at a $21.5B valuation and expands its Walmart deal

The round: led by Paradigm, WCM Investment Management and Layer Global. Fidelity, Uber, Tiger Global, J.P. Morgan, ARK Invest and Salesforce Ventures also took part.

Walmart: a new multi-year agreement adds 300 US drone delivery sites. The two companies run 21 sites today.

Fleet:

• Platform 2: home delivery, up to 8 lb within a 10-mile radius.
• Platform 1: long-range enterprise and government deliveries, up to 120 miles round trip.

Use of funds: expanding US manufacturing and hiring to build a nationwide delivery network.

Caveat: Zipline says its "share of delivery revenue" rose from 10.8% to 34.9% between March and October. It hasn't defined the metric, so treat the figure cautiously.

Agility Robotics goes public as the first pure-play humanoid stock

Status discrepancy. One report says Agility has already debuted on Nasdaq. Another describes a SPAC reverse merger still in progress that is expected to raise $465M from retail investors and a private funding tranche. The listing route is clear, but whether trading has started depends on which report is current.

Where the business stands:

• Digit robots are deployed with nine customers, including GXO, Schaeffler, Toyota Motor Manufacturing Canada and Mercado Libre.
• Most of the work is moving heavy totes, including more than 100,000 at one GXO site.
• H1 2026 revenue was $174K, mostly from related parties. Net loss was $362M over the same period.
• The CEO says the new capital covers current needs but won't say it is enough to reach self-sufficiency.

What the valuation depends on:

• $300M in "planned contracts" from 30 undisclosed customers for Digit 5. These deals depend on unspecified throughput, uptime and placement-accuracy targets. It is unclear whether any of these customers are also investors.
• Digit 5 hasn't been shown publicly. A demo is promised at CES 2027, with wide availability planned for late 2027.
• Claims to treat cautiously:
• The roughly $100K in annual savings per robot is a company projection based on Digit 5's untested performance.
• The 98% placement accuracy on heavy loads is a company figure.
• Like most humanoids, Digit cannot yet do complex manipulation.
• Pilots and capacity: proof-of-concept pilots cost customers $500K, and four had signed as of May. Stated factory capacity is 10,000 units a year, but no production targets were given.

Takeaway: Public markets will now test whether humanoid robots are a business or still a research program funded by investors.