Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56bd154be968c3e…

MALICIOUS

PDF

82.1 KB Created: 2021-05-21 13:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 7fea3d48b555c6ec778b02ce93d51fed SHA-1: 99de7b33d2a412f095f975617674f8d67a6a84f5 SHA-256: a56bd154be968c3e894c6426cdf21904f8515d03be6f087ec2b52e3078f28b68
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body contains garbled text, indicating it is not intended for direct user consumption but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/a6a3d2b2cdb4c40b6a0305ccba5b54c3/divepezofalijudusabupiga.pdf In PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4b741b07e---jonotawovaniz.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/cb0356bee63ad9024c143d97f477b36c/pubisoguje.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/89480961643.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5js24ve2ttaf36u9kf976pgec1/62240503808.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608417a89478d---21768104653.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2befc4e54---titewadipivanujutef.pdfIn PDF document text
    • https://www.groupenahno.com/wp-content/plugins/super-forms/uploads/php/files/ubphq20tb16ovmlfsh3151ualt/29774309957.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/vglc9b9g9mu5aqgcniip3mq6uk/98691613357.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/6a1b3ea017c1747654e5863ae39b769c/61835146908.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/8003642f3b61924f54be78b24109f06f/nujakuna.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/0386f9369a4487c26c6fa7dffbba5e1c/miranabifakodabofox.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+use+algebraic+identitiesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD932 5184 bytes
SHA-256: eb7dd0117393fbc503fd8687a54e201087c9bf2538123fa7757cbb303436bf2d
font_01_sfnt_off0000eae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE9 12428 bytes
SHA-256: 879ec7e394d30ba24ef51a3a1f00a0b594ddae30257096821097d5402286c85b
font_02_sfnt_off00011576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11576 16384 bytes
SHA-256: 73162f3bcfddf7b1ed773025b81c200b68bdd19b4dfdddc8460e96dec9cb197d
font_03_sfnt_off00012b7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B7D 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71