Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fc615359cb38623…

MALICIOUS

PDF

76.8 KB Created: 2021-03-31 05:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 1733bd3787a82e16e8117c469c7788b5 SHA-1: dac53e7ff426c1bb4c1f6d9a3f725092ce89536d SHA-256: 1fc615359cb38623a6f326f77138683f5a37d77e893e121f7bc1ebe0f3195fda
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URIs that point to other PDF documents, likely for SEO manipulation or to distribute further malicious content. The presence of multiple external links on disposable hosting further supports a malicious purpose.

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://botokaw.ru/wix?keyword=identity+v+apk+pc PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4470688/normal_6059e903d242c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474471/normal_600c72e8274d2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480403/normal_5ffcb48372c21.pdfIn PDF document text
    • http://jiwitoletazadag.iblogger.org/magazine_size_photoshop_template.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464303/normal_60540798d3cba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422627/normal_6024071818cc5.pdfIn PDF document text
    • http://gidepel.22web.org/surelosuv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444852/normal_604d7f0c894fd.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://6997f972-013f-4c6f-ac95-4179ba17a557.filesusr.com/ugd/549e1a_fb5494bbbf864cf794b3a532a42f9aa0.pdf?index=trueIn PDF document text
    • http://novotufimaxanu.epizy.com/37233685348.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ba6c8052-c174-4a24-9664-77aafe8e825b/14598953341.pdfIn PDF document text
    • https://d17f4099-ecc1-42b1-9c73-51521793457c.filesusr.com/ugd/4a2613_fc0166ca93064c2eb00427487257812e.pdf?index=trueIn PDF document text
    • http://daparetefofan.epizy.com/define_curriculum_development.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab51dcf8-252b-4dce-a46b-0f05d9d2d400/how_to_open_carbon_monoxide_alarm.pdfIn PDF document text
    • https://8641c524-1fb5-4292-87ed-dd72f64d6c22.filesusr.com/ugd/9b7d8a_d9c4d89f42cb41a0a7ab344d7925a7c6.pdf?index=trueIn PDF document text
    • https://e691ad07-92dc-45fa-af10-8929b4045ede.filesusr.com/ugd/87b9a8_ba50a35e4c66479dbb0d3dfc0e79f170.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c21c5fa7-0956-4a13-8e4f-9496b706c990/lenegaf.pdfIn PDF document text
    • https://6e678f60-abc6-404c-883a-cd1729fdffee.filesusr.com/ugd/e4291f_9c0ebcc540994b91addee5fcb6d03b3e.pdf?index=trueIn PDF document text
    • https://a9d1d3ec-13fa-4b7e-abe1-abe2c2ba1301.filesusr.com/ugd/f83029_4a8d387552ad47ddb159e713c9704e9c.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_off0000e5b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B2 2952 bytes
SHA-256: cb9072f881c1fe0ad8900bbcc5a20a23fabb306412f64e001cac76c2a9509f2c
font_01_sfnt_off0000f041.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF041 4924 bytes
SHA-256: cc21ae73f641950cec345b23dc4a030849784598e46318cf78dcc058e8bebc5c
font_02_sfnt_off0001012a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1012A 10812 bytes
SHA-256: 1b87f7e274d085ddcb16ab4b5e32d44395ce437c0e7002667a95e03f08f87c6a