Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d7c952ddba83c51…

MALICIOUS

PDF

44.7 KB Created: 2020-08-04 22:46:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d6d03fbcda46beb5664a8c1da25b43ae SHA-1: dcef78ef2b471ee3f9320cf1922f2bdff5cfd84d SHA-256: 4d7c952ddba83c51e9b5e77cf6e321a44c2ad1e008cd9cf5c55887fb4b0e5872
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, identified as a 'PDF SEO Link Farm'. One of these links, 'https://ttraff.ru/pify?keyword=bayesian+reasoning+and+machine+learning+barber+pdf', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains references to this URL and other PDF links, suggesting an attempt to lure users to malicious content. The ML classifier also strongly indicated maliciousness.

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=bayesian+reasoning+and+machine+learning+barber+pdf
    • http://files.tcfdstaff.org/uploads/1/3/0/9/130970022/ed462dff.pdf
    • http://files.matsusokankarate.org/uploads/1/3/2/6/132682542/nozowan_xosulemej.pdf
    • http://files.jocelynjacobson.com/uploads/1/3/0/8/130874394/pinatuzavebufumobe.pdf
    • https://cdn.shopify.com/s/files/1/0435/8995/9839/files/tosida.pdf
    • https://cdn.shopify.com/s/files/1/0433/6294/3144/files/9069597441.pdf
    • https://cdn.shopify.com/s/files/1/0435/0076/5336/files/46097840860.pdf
    • https://cdn.shopify.com/s/files/1/0432/1381/5966/files/nefagajekezexow.pdf
    • https://cdn.shopify.com/s/files/1/0428/6296/8991/files/47723029292.pdf
    • https://cdn.shopify.com/s/files/1/0450/4364/6614/files/bordeaux_guida_turistica.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/57032902602.pdf
    • https://cdn.shopify.com/s/files/1/0434/2428/4824/files/mixogatedes.pdf
    • https://cdn.shopify.com/s/files/1/0431/2370/3969/files/bufegafubekadera.pdf
    • https://cdn.shopify.com/s/files/1/0431/6997/2392/files/wubagox.pdf
    • https://cdn.shopify.com/s/files/1/0428/9832/5671/files/zinejujowokiradilawaxage.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000062b7.bin
e098dbe90f5fa927f6a1c454f7f60768e356f95322f9a7d49c584a78bee49132
pdf-font-stream PDF embedded font (sfnt) at offset 0x62B7 5568 bytes
font_01_sfnt_off0000756e.bin
7a173845159503de3b965bafa3fc386d92eb13ec98fef930c736b09c7da5a1f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x756E 10044 bytes
font_02_sfnt_off000097c7.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x97C7 4324 bytes