Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3f251d18c71c084…

MALICIOUS

PDF

85.3 KB Created: 2021-09-10 20:50:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a535dfca033f135bcae4cbb7218319de SHA-1: f563888c25b14e0cb2c82ccf398ba033fbb3e1e8 SHA-256: a3f251d18c71c084754703cd8bb6854db89f6a43e3beba6c7dc570cb731aa9c7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous external links, including a link farm on disposable hosting, and a heuristic for a visual download button suggests a phishing or malware distribution lure. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=app+cloner+mod+apk+latest PDF link annotation
    • http://unsersohn.ch/images/file/kexemeginimugonoxurid.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/72500403743.pdfIn PDF document text
    • http://areawifi.com/DESARROLLO/userfiles/files/xalasefotabotevow.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/92210917029.pdfIn PDF document text
    • http://copingconversations.com/userfiles/file/kutavowutegevalelowe.pdfIn PDF document text
    • https://tigapilar.com/upload/files/faxojozozuturapipokafu.pdfIn PDF document text
    • http://niktid.ru/userfiles/file/maxujudu.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/dabategelabupulifep.pdfIn PDF document text
    • https://hsdinstruments.nl/uploads/files/getojawebomapetupad.pdfIn PDF document text
    • http://tolaniprojects.com/userfiles/file/bijupamovalin.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/94160704719.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/90197345553.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/begutazuxunuputikasilux.pdfIn PDF document text
    • https://searchlink.org/userfiles/file/12089828967.pdfIn PDF document text
    • http://ossokahve.com/upload/file/15704842342.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/7376027882.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/87736296595.pdfIn PDF document text
    • https://uppersanduskyrotary.com/cms/files/File/dasamaw.pdfIn PDF document text
    • http://raczcsalad.hu/files/86699345107.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/dowawifaleduzubutu.pdfIn PDF document text
    • https://parkettworld.com/upload/files/2763287764.pdfIn PDF document text
    • https://aromamarketing.md/img/files/12942260207.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f79e148c11---sopezo.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161350a091f5b3---38093540811.pdfIn PDF document text
    • http://proximeo.com/ckfinder/userfiles/files/lefeposoxazepafamasebogip.pdfIn 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://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_off0000e5fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FA 18824 bytes
SHA-256: 65436a6c24f2e16d9d1ed41b289754001df434bcf529f0fa94b159ffe3ccbc76
font_01_sfnt_off000116a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116A6 10656 bytes
SHA-256: f759864e4a8e5ece6899610e314472a267e8444d3c312c0bed76fdfcf7472575
font_02_sfnt_off00012f26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1