Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c5cd4ea5fcdf91f…

MALICIOUS

PDF

77.3 KB Created: 2021-05-19 12:31:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9188d876c704f1b61dc332c7fc1a68d2 SHA-1: 9c4c24e42be049b29d8fdc3c4bc801efad8283a5 SHA-256: 7c5cd4ea5fcdf91f79898a49a8b5e2d87d52dc1312ef311739ffc6d66d5cc408
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many of which are part of a link farm designed to boost search engine rankings. The primary URL, https://nipisod.ru/strik, appears to be a malicious domain associated with phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nipisod.ru/strik?utm_term=how+many+exams+for+ccnp+security
    • https://fafofezun.weebly.com/uploads/1/3/4/3/134338513/puwufetelev.pdf
    • https://cdn-cms.f-static.net/uploads/4490930/normal_6060efa9dc345.pdf
    • https://cdn-cms.f-static.net/uploads/4394061/normal_6017551fc14f9.pdf
    • https://static.s123-cdn-static.com/uploads/4487424/normal_5ff669e564ef2.pdf
    • https://timodidub.weebly.com/uploads/1/3/1/3/131379596/kovenafokedowejipula.pdf
    • https://static.s123-cdn-static.com/uploads/4386828/normal_5fcfb70fbd89c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/203a4d37-abbb-4d0c-9fa7-9fabbe166f2b/81468500194.pdf
    • https://uploads.strikinglycdn.com/files/bf5ffe00-79b1-4fe7-8015-0245ede0e148/35723924596.pdf
    • https://uploads.strikinglycdn.com/files/e4a87bd8-98cf-4058-8f67-91c0cecbeee7/71543063223.pdf
    • https://uploads.strikinglycdn.com/files/6f5a4ec9-5265-4782-8f14-2955f84b10a9/oraciones_con_verbos_regulares_en_ingles_pasado_simple.pdf
    • https://s3.amazonaws.com/bipepezuwed/consistency_test_of_cement_lab_report.pdf
    • https://uploads.strikinglycdn.com/files/1986b776-ad54-424d-bf09-30bd7f4ab15d/what_fuel_to_use_in_coleman_stove.pdf
    • https://uploads.strikinglycdn.com/files/f0216222-ae8d-471e-9b17-fac871f822a2/how_long_is_fl_studio_trial.pdf
    • https://uploads.strikinglycdn.com/files/e0c3428f-1539-44f3-86ab-a3c5296deb72/mezarusuwelem.pdf
    • https://uploads.strikinglycdn.com/files/8a8edd44-0b6e-44c2-ab51-0109b346a7cd/how_to_get_coca_cola_kit_fifa_21.pdf
    • https://uploads.strikinglycdn.com/files/1523491a-afff-400c-a420-7ed2faaf4d83/revolution_2020_based_movie.pdf
    • https://uploads.strikinglycdn.com/files/1f9e1bc7-0b42-49b5-bf14-92efbb9a24ac/unit_3_parallel_and_perpendicular_lines_worksheet_answers_key_geometry.pdf
    • https://s3.amazonaws.com/nawuvud/pelabenit.pdf
    • https://uploads.strikinglycdn.com/files/4f0e7a9f-1d00-4c7c-af49-02c66e3f74ca/19135104263.pdf
    • https://uploads.strikinglycdn.com/files/e0a29e56-4a5c-4857-b43b-6bc0e90d345b/44462355213.pdf
    • https://s3.amazonaws.com/fapaga/9482496770.pdf
    • https://uploads.strikinglycdn.com/files/07c1d572-e242-4924-ac79-7de811eac8df/zuzeretewatigidu.pdf
    • https://s3.amazonaws.com/vibasujefir/auto_clicker_automatic_tap_pro_apk.pdf
    • https://uploads.strikinglycdn.com/files/ec7ae01e-35da-4735-9f38-08bf848b8438/kakulikifase.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eed0.bin
c306836401917867a02110c907361f2a2aaad16dade933eb95956d8e40822de9
pdf-font-stream PDF embedded font (sfnt) at offset 0xEED0 5352 bytes
font_01_sfnt_off00010107.bin
cf1cfe2a642be19f221c527f557dca0bee613f05440cc4837ead056b3ee48623
pdf-font-stream PDF embedded font (sfnt) at offset 0x10107 11344 bytes