Malicious PDF — malware analysis report

Static analysis result for SHA-256 a626ecdcc6856a13…

MALICIOUS

PDF

69.6 KB Created: 2020-11-20 03:50:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4befd13fdd689ed676481ae96573d751 SHA-1: 12fbf4324fd9212a03d526909110e921f1d25507 SHA-256: a626ecdcc6856a1377aec30845470b011fd7c87d8ce27fb87474e691043986a1
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to disposable domains and link farms, indicating a phishing or malware distribution attempt. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic confirms the presence of a link farm on disposable hosting, suggesting a tactic to obscure the ultimate destination or to distribute multiple malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://trafffe.ru/aws?utm_term=tablelayout+trong+android
    • https://xifobosakup.weebly.com/uploads/1/3/2/8/132815359/205644.pdf
    • https://cdn-cms.f-static.net/uploads/4454303/normal_5fb2ccc7a0552.pdf
    • https://cdn-cms.f-static.net/uploads/4413462/normal_5fa5d199b4fd3.pdf
    • https://kuvikupomudu.weebly.com/uploads/1/3/4/4/134457818/bazepezuwiluvu-nipuzofu-jajelodon-ludagi.pdf
    • https://jesasifewom.weebly.com/uploads/1/3/1/4/131453969/2080317.pdf
    • https://viweposedijul.weebly.com/uploads/1/3/1/0/131070314/84221afd4b04.pdf
    • https://cdn-cms.f-static.net/uploads/4381551/normal_5f91e03867bd6.pdf
    • https://sazojowob.weebly.com/uploads/1/3/4/3/134351878/zawofejuvikefizu.pdf
    • https://sepenunaxob.weebly.com/uploads/1/3/0/7/130776074/jojepuv.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/xifabilejilab/20564883083.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c8fd.bin
591e343d08c9c9797c79d29c677ce6200119d05e569c02de1a9c6aa00695cb69
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FD 5004 bytes
font_01_sfnt_off0000da0e.bin
6d2a3a16cc464ce72cf05976c7f96a31c93af2202e0dc760c37a694345e222ee
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA0E 1800 bytes
font_02_sfnt_off0000e29e.bin
ad7d7561536d666c6155639646b35b371e4d8149711fdbf05d3ebc34f7c788da
pdf-font-stream PDF embedded font (sfnt) at offset 0xE29E 11348 bytes