Malicious PDF — malware analysis report

Static analysis result for SHA-256 c84231e93c3de470…

MALICIOUS

PDF

74.2 KB Created: 2021-06-06 19:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 623ebd6c408beb0713415c1539549275 SHA-1: d536185d4ae3bfd37eb160795d2b16db5843156c SHA-256: c84231e93c3de47071f03498824e28f53ab603a55ce318e6e42924f7c2468301
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body, though heavily obfuscated, appears to be a lure related to educational content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://wastran.ru/pbw?utm_term=list+of+transition+words+for+high+school PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4481424/normal_5ffa16a23555e.pdfIn PDF document text
    • https://lesinagin.weebly.com/uploads/1/3/1/4/131454304/diwosodixixijegugu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495550/normal_5feb51a3c002a.pdfIn PDF document text
    • https://pugufatafa.weebly.com/uploads/1/3/5/9/135967981/lilowu.pdfIn PDF document text
    • https://pakurematumomu.weebly.com/uploads/1/3/4/7/134764434/6139d6510e.pdfIn PDF document text
    • https://sobopagep.weebly.com/uploads/1/3/0/8/130873740/e54778b500fd.pdfIn PDF document text
    • https://ruparowix.weebly.com/uploads/1/3/4/3/134350000/dorer.pdfIn PDF document text
    • https://munuradon.weebly.com/uploads/1/3/1/8/131859370/nitenalexugadeviwaze.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xibosini.pbworks.com/f/adjectives_and_adverbs_easy_exercises.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1eb4d68-8b45-4a99-9913-d90fa1f3e6ba/jokaxemukilejevawegamo.pdfIn PDF document text
    • http://jebodigezev.pbworks.com/w/file/fetch/144697986/17369327290.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb301b78-31d5-458c-9d06-6afec72b1658/how_much_can_a_2015_subaru_forester_tow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c5f0554-47af-4281-a761-263244dd2aec/xozejorugitugivowatok.pdfIn PDF document text
    • http://tefimemovem.pbworks.com/f/siwugozarofibilopegolej.pdfIn PDF document text
    • http://jiboduxoguv.pbworks.com/f/adhyaksha_in_america_kannada_full_movie_online.pdfIn PDF document text
    • http://guronavageba.pbworks.com/f/how_to_request_cheque_book_in_sbi_saral.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dbb03a4-dea3-4c63-906b-1e4f92ce7c13/prentice_hall_biology_online_textbook.pdfIn PDF document text
    • http://bupataved.pbworks.com/f/74449849172.pdfIn PDF document text
    • http://bujolajoxek.pbworks.com/f/o_livro_dos_mortos_em.pdfIn PDF document text
    • http://gudotoxej.pbworks.com/w/file/fetch/144525006/thermodynamics_an_engineering_approach_7th_edition_si_units.pdfIn PDF document text
    • http://zezimin.pbworks.com/f/tasotozofagetovim.pdfIn PDF document text
    • http://varulemenel.pbworks.com/f/why_is_my_ipad_not_finding_my_airprint_printer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7c6a9ea-3639-4d32-b532-69d857fdcfcd/11624781748.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://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/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_off0000e58c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58C 5316 bytes
SHA-256: 8d0a310e7985578265d9123223dc51809a5a89d4715e32333f09c308865a13cd
font_01_sfnt_off0000f7b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B4 10236 bytes
SHA-256: a00a1663a02d5c47e54b9f0e62f1dc488492e124572d5bb5909d7001546cd359