Malicious PDF — malware analysis report

Static analysis result for SHA-256 c771e1d403ecf78a…

MALICIOUS

PDF

82.5 KB Created: 2021-06-19 17:57:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 1b3dbf62207fbc098f3bba83b3ac232f SHA-1: ba53e4efe36dbcaffb0ef4bb3c56b5109a7d82bf SHA-256: c771e1d403ecf78aca8ae8d39b24e9e9cc3a1dd1f6108cdc3eeb0ddfe96daf81
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites, likely serving as a distribution point for further malicious content or phishing attempts. The presence of multiple external URIs and a link farm structure strongly suggests an attempt to lure users to malicious destinations.

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 http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d3730bcfb---dusekawogegiruzegid.pdf In PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/428a462d36494dd2ce3c1948bd35438b/deliwuwogubijud.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c5397d39a0c---72939227972.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/881562ce383f0748f61c9c317d044f2d/futawamarunitajub.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/dulutewokap.pdfIn PDF document text
    • http://best-infosystems.com/userfiles/file/72921048004.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/2ba4581e362965182626499c808395a5/bekumikipadok.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/0384180ebddc9e10773714bc577b40d0/xuwulurerulinifepivuzuze.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/96acf8aa723e65a4536dfe5b7594cb54/saguvonat.pdfIn PDF document text
    • http://smit-electronic.hr/upload/datoteke/relujozogitusajafup.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e425e96f4---xiguvilasubopemeputiwizam.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/juwiwovedewujadidemofib.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947cda92f41---51953717722.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ba20dcf10c9---jufubikujikavelogibepaz.pdfIn PDF document text
    • http://congtrinhnhaviet.vn/upload/files/11249136611.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=rajkumar+bhakti+geethegaluPDF 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF66 5208 bytes
SHA-256: 9e55dde42cd05b90a4dcd15bd6a8005b5bbab2e527201f1fcca68f7cedb9ddd5
font_01_sfnt_off00010101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10101 14348 bytes
SHA-256: 8e4410e45ca8db7db2c0c2259b747b0df63c5547b13317181fdf35d91d4b7a89
font_02_sfnt_off00012fad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FAD 3452 bytes
SHA-256: 4582e1d9e456eb1a02490893a52a3ca83cfdcb09ef3d2f1bd759cb8aef2c2653