Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbe388d09d1f5dea…

MALICIOUS

PDF

83.2 KB Created: 2021-08-17 11:35:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 677b6c267231b8317e5f1cdddf4507c1 SHA-1: 55a850713b45baca98f9dfe05d977c7fd5ee0020 SHA-256: fbe388d09d1f5deab2ba0e74c3834eb719085d19c7fb2e4218b0dd882ec37d95
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised or disposable domains, as indicated by the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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 http://sciattella.net/images/file/digozuw.pdf In PDF document text
    • http://guilfordvikingsclassof81.com/clients/4/47/479b0a304b4cdce99dfe3eda73a59016/File/2766997263.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8314c49ddf---vunaxozejofaw.pdfIn PDF document text
    • https://bczenekar.hu/files/file/2115317239.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/2812177276.pdfIn PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/d38c5600dc238c982ed082d71bef5e86/76916947858.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/xibewadi.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16078a98412b61---fawutabujevegefega.pdfIn PDF document text
    • https://ctapigroup3.com/contents//files/10942015914.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/fofuzikuwatuwabejimebo.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/9jr34ri916gh49tvm7prs9kj8f/65499826276.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/e6de94078401d2eae62397275463fa0a/46114571099.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b7slvvrncqppbgabiq25id2d27/pixemafawexodimezid.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/eb6c11bf65e03a40167f58e8eb9648d6/22592346328.pdfIn PDF document text
    • http://lechioutdoor.com/userfiles/file/xotavilowax.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/bibaxerud.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/6271463835.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/4o4iqbaobej543g4f80dqtc855/85072839014.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3f66ac5a4---lewinatur.pdfIn PDF document text
    • http://szrealty.net/uploadpic/2021-5/file/2021052602521573499.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/5a3ec4ef7008cf6e958b94f0068b9b30/wumelafovimozanumo.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091dc69be0f0---31599392507.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f27a8bd8f4b---83414994254.pdfIn PDF document text
    • https://kawanmto.net/contents//files/32173563483.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/niretu.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/05/24/file/20210524_230918_160.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=what+should+i+compare+and+contrastPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE176 16864 bytes
SHA-256: bbe72c4c11afac57893add0e17c1d713f3b2151597195a4e22139ebee0010a25
font_01_sfnt_off00010d4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4C 10872 bytes
SHA-256: ae7fe79c91440d7979bca2025a2e13f244fc0c0a8b5e1dee772f0ec6be5a9f12
font_02_sfnt_off0001263e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1263E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1