Malicious PDF — malware analysis report

Static analysis result for SHA-256 31515bd7bfe86030…

MALICIOUS

PDF

61.5 KB Created: 2020-11-11 21:24:53 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 98d2c8fcb8cb2e78ccb49db099485b3c SHA-1: 5c8485f8a393a14341b605d5cc62eeb966f6ba23 SHA-256: 31515bd7bfe8603030f3dfb2f1b6b230f99a10bb42b9a55057b78d62fecd5cc3
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one heuristic specifically identifying it as a 'PDF_SEO_LINK_FARM' containing a mass of external links. The ClamAV detection and ML classifier strongly indicate maliciousness, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm suggest an attempt to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/123?utm_term=end+behavior+practice+worksheet+answers
    • https://mumixopid.weebly.com/uploads/1/3/1/8/131872042/xisewazadim.pdf
    • https://purolejomi.weebly.com/uploads/1/3/0/7/130776639/ralovitinameli.pdf
    • https://zunotebizi.weebly.com/uploads/1/3/4/6/134648513/dipokotasuk.pdf
    • https://zosupexaduj.weebly.com/uploads/1/3/0/7/130738593/xarevovoge-zudoxabuwugikuv-xuwewevozogaz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/63661ca9-30e1-464d-8e81-b27e259ce6dd/xaluxinakoluravevoterilud.pdf
    • https://uploads.strikinglycdn.com/files/a234a026-e30c-4d50-ae3c-d2bfe5a7bda8/my_hero_academia_episode_68_release_date.pdf
    • https://s3.amazonaws.com/lakadutof/lavekamovufekubimiluwipa.pdf
    • https://uploads.strikinglycdn.com/files/64a2eba1-8d02-4f43-908f-4b319f3e69ad/msn_outlook_mail_account.pdf
    • https://s3.amazonaws.com/kovilowab/45821590360.pdf
    • https://uploads.strikinglycdn.com/files/91c5008b-3ff8-481f-abe6-d597900e1013/danielson_domain_4_artifacts_examples.pdf
    • https://uploads.strikinglycdn.com/files/45971f92-1f8c-49c3-8112-c8589cade246/73218794926.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_off0000b41c.bin
bd55326c157d1511c436b8a9437610f72bf3ec9f552d74d84850ccc04c6fc3d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xB41C 5440 bytes
font_01_sfnt_off0000c6a9.bin
7be17ff0984385aebb49b94f00606d40320b094af1954c3e5b43100773920419
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6A9 10188 bytes