Malicious PDF — malware analysis report

Static analysis result for SHA-256 53aa04a7de7fcfef…

MALICIOUS

PDF

85.4 KB Created: 2021-03-14 16:45:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 699ec8a116ad02e9b8f3aed5316f56e5 SHA-1: ed28a5b666ced075d706bb3656d56fbf67ca9547 SHA-256: 53aa04a7de7fcfef4d9f4c2e08ebc53958bd1da64d772d07b761c8ec434b70d0
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs pointing to other PDF documents hosted on disposable domains. This behavior is often associated with SEO manipulation or distributing further stages of malware. The presence of multiple external links and the use of disposable hosting services suggest a campaign to distribute or obscure malicious content.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://vilenefex.ru/award?keyword=les+analyse+biochimique+de+sang+pdf PDF link annotation
    • https://bijawodit.weebly.com/uploads/1/3/4/8/134883407/6402209.pdfIn PDF document text
    • https://pesadosopovito.weebly.com/uploads/1/3/4/2/134235692/4740a9c4462b.pdfIn PDF document text
    • https://radefikifuru.weebly.com/uploads/1/3/4/7/134723330/vuwebifigedakebozeb.pdfIn PDF document text
    • https://wanuwajazil.weebly.com/uploads/1/3/4/8/134899981/018bc74271b.pdfIn PDF document text
    • https://zumugerajezu.weebly.com/uploads/1/3/1/1/131163828/towoxubojuwigus_ligofisanigebos.pdfIn PDF document text
    • https://galixasuja.weebly.com/uploads/1/3/4/5/134518214/vivutaz_xelavib.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472766/normal_60163c2244d69.pdfIn PDF document text
    • https://bolukuja.weebly.com/uploads/1/3/0/7/130739437/7839196f29c1.pdfIn PDF document text
    • https://xowitato.weebly.com/uploads/1/3/0/7/130776358/momasipegapoza.pdfIn PDF document text
    • https://nutovavodus.weebly.com/uploads/1/3/4/0/134012609/bepupe.pdfIn PDF document text
    • https://jotulamopusojo.weebly.com/uploads/1/3/4/4/134465369/300635.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485828/normal_600473bddf49a.pdfIn PDF document text
    • https://rorobobadewa.weebly.com/uploads/1/3/1/1/131164171/bimufix.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://43081b45-6e48-4b43-b724-9328fda377ae.filesusr.com/ugd/26481d_80fdb772d2c546e8895018a76b2f0a8a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3c75c46-1ab3-4005-8e83-1db69b861433/myles_munroe_sermons.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2755fc1-aa2c-4a61-b068-a1e55d1aa766/garmin_montana_600_vs_700.pdfIn PDF document text
    • https://07e0a16e-b77d-475b-b724-88bbaedb347c.filesusr.com/ugd/8e9e2f_96dccc2ba3154b41822eced79d0897a9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0f57d15-4aea-4fdc-b9c7-fd5dd35f45da/mimew.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f80b5f3c-d513-4ad5-b3a0-1ca443d07594/satuginalewokeluridinares.pdfIn PDF document text
    • https://d497f082-4895-42de-a72c-038d9367c8a3.filesusr.com/ugd/8e727b_be07c5cab89b44b6a44f61850a6295b1.pdf?index=trueIn PDF document text
    • 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_off0000ff67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF67 5584 bytes
SHA-256: f7f3dc132bdd8be7e98dcf056db780ef312b88f8007779611be72d9247468f07
font_01_sfnt_off00011231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11231 12336 bytes
SHA-256: 35925375828962b8ab321decc11c5ac5c9ea7693a9d3ffa2b8c35ebf94158aeb
font_02_sfnt_off00013857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13857 4324 bytes
SHA-256: ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230