Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bf2737fe809fe99…

MALICIOUS

PDF

71.9 KB Created: 2021-05-25 20:55:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4ae7f3f657b36b756fdf4da5a8fa81f2 SHA-1: 55271686b5f790ec790c701f8fa7bba6e6571b66 SHA-256: 3bf2737fe809fe99c5a7baf00c8383ea4ec8c287d07ff1a3332f2efb5f4b8ebe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and contains metadata about its creation, but the primary malicious activity is inferred from the embedded URLs and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0e64a933f---juwora.pdf
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/0bf24caaae98f3dd1dd58e9dbae79bf4/tifamebasaxubigeku.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/59a0e2c9628c0c15974d80225e937c77/41820784407.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092705e48980---ferezumexolesudefij.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8645b1456---zopipi.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/2fc6a6b577f890f1d794901751f15647/lafidokopisob.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3425631af3---46757887203.pdf
    • http://adabaskimerkezi.com/upload/file/kokivab.pdf
    • https://aplusadvance.com/naver_editor/data/file/61352663382.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/0a9d0b46cb343599573e8cd8cd930303/rifutowevuzav.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eca2e36326---belapomari.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607b242da2162---47951232660.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16080a757cfc4e---39871709706.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/a8a16dda9014578305879c4b80cecbb7/duvewubona.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b151b270a---36947338080.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a429bf42765---89803060741.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=sector+is+clear+meme
    • 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_off0000d247.bin
2e667bafb8ac92ac0b54d4ea9fdd041bdc83ffd87ac8cc9f02ebcaa7786f591b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD247 4728 bytes
font_01_sfnt_off0000e247.bin
286feee683cf426a142d482ecc4f471475cb75f9d86cfb4fc77a9208e0547343
pdf-font-stream PDF embedded font (sfnt) at offset 0xE247 9964 bytes
font_02_sfnt_off0001041b.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1041B 4324 bytes