Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c37aca7de32e4b6…

MALICIOUS

PDF

49.4 KB Created: 2020-09-07 02:48:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 5dc8569eabb5ba95f5f65798aaf86b5b SHA-1: c491a0896ef0a452be0babac97dc16342b0f546c SHA-256: 9c37aca7de32e4b6c69b2f743eeb75c8949c5dae23208ec8dc1ec444ff00e058
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded links to a known malicious redirector, ttraff.cc, which is disguised as a free dictionary download. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms this, and the ML classifier strongly indicates maliciousness. The document body, though heavily corrupted, contains fragments of the lure text and the malicious URL, reinforcing the phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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.cc/wix?keyword=dictionnaire+anglais+fran%25C3%25A7ais+gratuit+pdf In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://static.usrfiles.com/ugd/1479de_f01a0145251d4d1eb29489a66c1872ee.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/762c1a_0f4573a17c0b4069927b89ea46a3ad54.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/f8de3e_edfa8a2c8e494a39ae1302fa6891ba40.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/23b571_461b7641829042e383f3071f3e8e8ee2.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/041b56_50cc588d51fb4957990988c47ac09686.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/7948/9950/files/bahnwrter_thiel_knigs_erluterungen.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/9340/8409/files/zuxavisupubipodenujarefak.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/0213/3667/files/basic_probability_exercises_and_solutions.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/9201/6280/files/behaviorist_psychology.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/74c34a_0a53e73b14b545978f942928b85ba0a9.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/8e1900_25c567ef0b624a5985a44481e09c19a4.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/5b5da7_a548b2e15cfd4f31859e06313c0fd479.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/c3f59f_ef2598aa56e844fd94311ae71de62b52.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/87a178_819868f1e6a14e5f931739a6ac949a55.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/81b904_e4a4091b700f44369ce2b6996fa038b3.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/defdb4_f289023e62e344e09c9c3002c9ea2737.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/a13bc2_451c6f382a7a40d7a5d25e73642e70c6.pdfIn PDF document text
    • https://static.usrfiles.com/ugd/2ddd39_6e01c29ff6104c62a4228ded33af3507.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00008109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8109 5504 bytes
SHA-256: 8007d1a437e6097c4d452ee1b0c1ebb90b0459c7e71242273ae14a4e07519976
font_01_sfnt_off00009392.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9392 12684 bytes
SHA-256: 9b17559d8dfd02524594e9ef7fb203cab2e645d35d185f3e05894dfc44a366a2