Malicious PDF — malware analysis report

Static analysis result for SHA-256 249336b88198aee5…

MALICIOUS

PDF

73.6 KB Created: 2020-11-19 06:41:58 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a8fb7629164279fc3443f8205a34e1f2 SHA-1: 7caf81d0bf5c65c13b45ab826f6d209c4ff35eae SHA-256: 249336b88198aee5cae1687fb6521ae963aea49e63e835f236294ff9b3544555
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a ClamAV signature and an ML classifier. It contains a large number of external links, many pointing to S3 buckets and Weebly-hosted PDFs, suggesting a link farm or phishing attempt. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, with one example being 'https://s3.amazonaws.com/mijedusovineti/rocket_propulsion_elements_ninth_edition.pdf'. The presence of embedded URLs and the overall structure strongly suggest a phishing or malware distribution vector.

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://trafficel.ru/aws?utm_term=avg+free+full++for+mac
    • https://mekuxiwefajup.weebly.com/uploads/1/3/0/7/130739023/5829299.pdf
    • https://cdn-cms.f-static.net/uploads/4501380/normal_5fafff790f692.pdf
    • https://cdn-cms.f-static.net/uploads/4369322/normal_5f914f0978237.pdf
    • https://tetegewa.weebly.com/uploads/1/3/4/7/134761184/gusubinevuxu.pdf
    • https://misutinulil.weebly.com/uploads/1/3/1/4/131407711/fd46e57ac9e.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/mijedusovineti/rocket_propulsion_elements_ninth_edition.pdf
    • https://s3.amazonaws.com/kagedatabujo/indestructo_tank_3.pdf
    • https://s3.amazonaws.com/zemigiduwagafu/gerivavezi.pdf
    • https://s3.amazonaws.com/nigimul/1300790415.pdf
    • https://s3.amazonaws.com/panokojol/complete_savings_refund_form.pdf
    • https://s3.amazonaws.com/gogunabones/acid_and_base_ph_simulation_lab_answers.pdf
    • https://s3.amazonaws.com/vuzotisenixava/67864079487.pdf
    • https://s3.amazonaws.com/kulinisokakewi/under_armour_team_uniforms_builder.pdf
    • https://s3.amazonaws.com/fejififimaketo/vujumokulupufuvo.pdf
    • https://s3.amazonaws.com/lebaxa/chakravakam_songs_free.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_off0000e458.bin
39663824d24d99992687279c105866886a474b75eed76d2d583a78f857566bcc
pdf-font-stream PDF embedded font (sfnt) at offset 0xE458 5072 bytes
font_01_sfnt_off0000f591.bin
fc7337f20c5e90bc24faaed5f392609b5965e732d1f513ac9dc0a6819b0121c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF591 10568 bytes