Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8831791138eebbe…

MALICIOUS

PDF

67.7 KB Created: 2020-11-19 03:15:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 61e1e7ca9821b2720b6ccd2a3b0d7cd5 SHA-1: 92afd5c9dd26df545eb5a104d7eea101dc047b18 SHA-256: c8831791138eebbe6f5b4fcd0b8b44b6142d0731a628f56350693e778ddcd5f6
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, with a critical heuristic firing for a PDF link farm. One of the primary URLs points to trafftec.ru, suggesting a potential phishing or malicious redirection attempt. While no scripts were explicitly extracted, the PDF structure and link farm indicate an attempt to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://trafftec.ru/strik?utm_term=libro+el+hombre+mas+rico+de+babiloni
    • https://noxutepobop.weebly.com/uploads/1/3/4/5/134510102/jamifujobu_vedepe_vopusowetixu.pdf
    • https://sanivuledaxefe.weebly.com/uploads/1/3/4/2/134234591/bimaloteti.pdf
    • https://dirigesibujov.weebly.com/uploads/1/3/0/9/130969991/bitunuz_jizugelobo.pdf
    • https://mokitapakajare.weebly.com/uploads/1/3/4/8/134885173/0b673daa.pdf
    • https://gizazegixewaner.weebly.com/uploads/1/3/4/5/134596748/a76013c6d49.pdf
    • https://satupagewamikim.weebly.com/uploads/1/3/4/5/134584558/0f28b4dd2.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/05bb7156-448e-4e5a-902d-66bd7be8ecec/frases_mas_comunes_en_ingles.pdf
    • https://uploads.strikinglycdn.com/files/63fee09a-4131-4a69-8256-8429df91f7c8/90223020442.pdf
    • https://uploads.strikinglycdn.com/files/e24ae7c1-95a0-4133-8d5c-eb8786815253/vesikav.pdf
    • https://s3.amazonaws.com/lorifumofelu/wacom_cintiq_22hd.pdf
    • https://s3.amazonaws.com/lakadutof/neet_2018_answer_key.pdf
    • https://uploads.strikinglycdn.com/files/5617b93f-817a-4117-bba8-02e8e366461a/91229654509.pdf
    • https://s3.amazonaws.com/badodemebo/2268405450.pdf
    • https://uploads.strikinglycdn.com/files/2e974aa5-3c11-4d21-9c22-75c423941c6f/list_of_english_words_with_silent_h.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_off0000c8ff.bin
0d77593cf5c755548545f343f19c6df17f0b4e4dd6e63eab92e5cf0294cb32f7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FF 5260 bytes
font_01_sfnt_off0000daa6.bin
3898b99c112a0808d4c12a4a9b8623e751b04d6ed7bb4eec24508e000973dab4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAA6 11492 bytes