Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff787fc7e5cebbfb…

MALICIOUS

PDF

71.6 KB Created: 2021-09-26 07:15:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 0b1aa388d817f747f7ec38fcfa030531 SHA-1: 119eccbe06d736b038030f0aa5e2bb4d0eb34aa3 SHA-256: ff787fc7e5cebbfb74f0635ef546598e2449cd7045a06a7b63828f3f9b3a920b
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains, indicating a link farm designed to host malicious content or phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links. The file's structure and the presence of many external links align with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://yenhuy.vn/upload/files/84002029149.pdf In PDF document text
    • http://teamtrinity.net/trinitya/file/49872521475.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/73502700741.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/36582339297.pdfIn PDF document text
    • https://hyosungulf.com/uploads/file/jofoxusunegexuta.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/88368424441.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/bimememavewuvapurujavi.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/6818295231.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/bafumolavuzupofa.pdfIn PDF document text
    • https://ozora.schaffsen.com/contents/file/karumulineturolimini.pdfIn PDF document text
    • http://studiolegalebisantis.it/userfiles/files/daresifozusamugasigaz.pdfIn PDF document text
    • http://sloplast.com/userfiles/files/72548259956.pdfIn PDF document text
    • http://mrs-edu.com/sribati/editor/uploadfiles/96629242972.pdfIn PDF document text
    • https://wietsevoermans.nl/ckfinder/userfiles/files/62346012670.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/c0eb098332fa23788149cdbf7cbc3a34/nipabafolakutis.pdfIn PDF document text
    • https://agape4u.org/userfiles/file/zanafewozibatirejorobenez.pdfIn PDF document text
    • https://sunnyrosesschool.com/userfiles/file/8280667109.pdfIn PDF document text
    • http://dubossari.es-pmr.com/constructor/dubossari/ckfinder/userfiles/files/weluzizewepas.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/10902006035.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/dozasu.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/samodezufuxakoge.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/76199272313.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=chemistry+ia+examplesPDF 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_off0000b1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1BB 18380 bytes
SHA-256: 5535a2faed76d1c02975a1ce0387ba01dc7f8ac407b39334ab150ccebef13805
font_01_sfnt_off0000e07f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE07F 10540 bytes
SHA-256: d5f18e3df6ec152cccacda427c8584e7fbd60a0b2191f3883370a281dbf1bba0
font_02_sfnt_off0000f890.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF890 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1