Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2cfc1b4e4cad8dd…

MALICIOUS

PDF

82.1 KB Created: 2021-05-27 18:01:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: af6df79cec9ee06a3d2172fc0dfcc952 SHA-1: 550e93bd831ffc787787eeafeea007d25abed706 SHA-256: a2cfc1b4e4cad8dd067c483c79dec8aef6e84d3b3c2b30fde64be39514a1a760
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to PDF files hosted on Weebly, suggesting a link farm or redirection mechanism for malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and extensive external linking are characteristic of phishing lures designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://ponafet.ru/strik?utm_term=paper+chromatography+lab+worksheet+answers
    • https://bafiredevidif.weebly.com/uploads/1/3/1/3/131384403/b86eb9358d37aeb.pdf
    • https://xipunozelizu.weebly.com/uploads/1/3/1/3/131382486/mubujogiwigexivowu.pdf
    • https://xuvodovujekezoz.weebly.com/uploads/1/3/5/9/135957716/domewipizo_gokikenetugepe_kemagugixeki_laravaxodumik.pdf
    • https://pevaluxuduta.weebly.com/uploads/1/3/4/5/134502983/2674fd.pdf
    • https://jurogewogil.weebly.com/uploads/1/3/4/3/134318518/607203e8ff8df9.pdf
    • https://xododasewa.weebly.com/uploads/1/3/4/6/134600374/355f52.pdf
    • https://static.s123-cdn-static.com/uploads/4484814/normal_5ffab04612e36.pdf
    • https://cdn-cms.f-static.net/uploads/4450719/normal_60110b6dd1e07.pdf
    • https://lanoxujuzon.weebly.com/uploads/1/3/4/6/134630121/fufekuse.pdf
    • https://bumipavadawafez.weebly.com/uploads/1/3/2/7/132710759/8969980.pdf
    • https://cdn-cms.f-static.net/uploads/4452595/normal_6044fd2fc1513.pdf
    • https://cdn-cms.f-static.net/uploads/4375700/normal_6034424aa3bc7.pdf
    • https://kigusokitog.weebly.com/uploads/1/3/5/3/135300221/7261435.pdf
    • https://wawotuxela.weebly.com/uploads/1/3/4/3/134352856/bujitatarij.pdf
    • https://dozetiwe.weebly.com/uploads/1/3/1/8/131856451/vemebifesopad_xukasu_bulobez_xuvojimasefiwe.pdf
    • https://cdn-cms.f-static.net/uploads/4471946/normal_603faa80a08ed.pdf
    • https://static.s123-cdn-static.com/uploads/4471488/normal_5fec38afe9c25.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/2f4f119f-7351-4461-b8df-abf475417258/english_to_bengali_sentence_translation_software_free_download_for_pc.pdf
    • https://uploads.strikinglycdn.com/files/db4e3d25-7d33-4b44-9fed-6b4ec8e6ad55/norse_mythology_loki_horse.pdf
    • https://uploads.strikinglycdn.com/files/5212940d-e4e6-403b-96dc-1bead725bb48/20_love_poems_pablo_neruda.pdf
    • https://uploads.strikinglycdn.com/files/06b4ee61-2c3e-432f-a1b8-73e5a4587a6f/fuwunupu.pdf
    • https://uploads.strikinglycdn.com/files/628845a9-2a0a-4469-be43-677da2847e0c/how_to_hack_shell_shockers_on_chromebook.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/
    • https://savannah.gnu.org/projects/freefont/
    • http://www.gnu.org/licenses/
    • http://www.gnu.org/copyleft/gpl.html
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efdf.bin
31d4dd97cf5147e6b059c24d0fa5ef82248f625d272ff84a9e6c0d2f8a785f9a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDF 6812 bytes
font_01_sfnt_off00010114.bin
403e775d717c12f272ff38aa5600c9821036279c0d115d48956692ca50b9883a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10114 5744 bytes
font_02_sfnt_off0001148f.bin
308166abd1d66b90f7282ed6bbb1ad0ad04052cc3fa9a4e8463ed0094fe0a1ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x1148F 11152 bytes