Malicious PDF — malware analysis report

Static analysis result for SHA-256 b319274232fe557d…

MALICIOUS

PDF

44.0 KB Created: 2020-07-31 07:10:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 30cf152ce59c084d086a4040ad88f46d SHA-1: 9153fc2e1c72ebf72beab1109d6cd87185ae2cd3 SHA-256: b319274232fe557d40fda9d10bbd68d13c0b11ccbdd12110bbf970038f2cdcbe
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 Malicious Link T1059.001 PowerShell

The PDF contains a high number of embedded links, many pointing to Shopify domains hosting other PDFs, suggesting a link farm for SEO manipulation. One critical heuristic identified a link to a known malicious redirector, ttraff.ru, which is presented to the user as a download for 'agriculture books pdf'. The ML classifier strongly supports the malicious nature of this PDF. No scripts were extracted, but the primary attack vector is the malicious redirection link.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=agriculture+books+pdf+download
    • http://files.ethelseducationalexpress.com/uploads/1/3/1/0/131071151/1097480.pdf
    • http://files.stupedhillbilly.com/uploads/1/3/0/7/130740573/mipod_riwafabikebuto.pdf
    • http://files.rustedrelics.com/uploads/1/3/1/3/131380546/d1d11f.pdf
    • https://cdn.shopify.com/s/files/1/0436/9724/2280/files/dirasewosesisiri.pdf
    • https://cdn.shopify.com/s/files/1/0430/9218/1145/files/sogifixitofotu.pdf
    • https://cdn.shopify.com/s/files/1/0428/8974/0441/files/72131976236.pdf
    • https://cdn.shopify.com/s/files/1/0434/8693/7253/files/xolanu.pdf
    • https://cdn.shopify.com/s/files/1/0430/4207/8877/files/79020815235.pdf
    • https://cdn.shopify.com/s/files/1/0430/8962/5241/files/kutexe.pdf
    • https://cdn.shopify.com/s/files/1/0430/1671/6437/files/47420052499.pdf
    • https://cdn.shopify.com/s/files/1/0433/8683/0998/files/73139707696.pdf
    • https://cdn.shopify.com/s/files/1/0433/2303/1720/files/35622917920.pdf
    • https://cdn.shopify.com/s/files/1/0427/9877/6487/files/84855289909.pdf
    • https://cdn.shopify.com/s/files/1/0427/7207/0556/files/dedefoduruwilidoj.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/20597849085.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006c4a.bin
22a14b7724befb7c416a64a1b5d62c3252e5ade0cf9f82dd5e4c3926da4afa3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C4A 5488 bytes
font_01_sfnt_off00007f0a.bin
53a10fb37e9e1f88fa46cf840a080c258879cdd98a9b2cfcecec38046e1c86e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F0A 10512 bytes