Malicious PDF — malware analysis report

Static analysis result for SHA-256 a317f20ef4071d26…

MALICIOUS

PDF

72.6 KB Created: 2021-09-27 09:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5c3cc7b17df95f0ff1acaba75b523126 SHA-1: 91ca6b7f97d1fb0e1cfc1c364318aeff41be6f43 SHA-256: a317f20ef4071d26ce589e084c726b900320274f5963cc8f7da5c2e412662c82
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a high likelihood of this document being used to distribute malicious content or phish for credentials. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nhaccugiare24h.com/uploads/userfiles/file/bupeviludazi.pdf In PDF document text
    • https://centaur.vri.cz/docs/files/lowiralolarumi.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/84719605624.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161419e30b283f---gepaxogoz.pdfIn PDF document text
    • http://ipsgroupjjn.org/userfiles/file/23739575684.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/dojelukokirunemub.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/50287222396.pdfIn PDF document text
    • https://mar3ol.com/Files/files/nufeparivirusamapumabufe.pdfIn PDF document text
    • http://planbmedia.hu/files/wazerimiteb.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/41000969772.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161352d483b734---75474095901.pdfIn PDF document text
    • https://nadrozmerne-sklo.cz/uploads/pigiredefus.pdfIn PDF document text
    • http://1yunnan.com/ckfinder/userfiles/files/15160914489.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/31763321466.pdfIn PDF document text
    • https://nbtele.com/en/cache/fck_files/file/kekom.pdfIn PDF document text
    • http://nguyenxuanhuong.com/upload/files/83569811108.pdfIn PDF document text
    • http://satcomlink.com/userData/board/file/93607892485.pdfIn PDF document text
    • https://www.theoakshealthcare.com/my_content/js/ckfinder/userfiles/files/74427952733.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/16234765271.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/44559204827.pdfIn PDF document text
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/lelizosowipadezotiju.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/52185786451.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/jonanapevaxixowofud.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///47440829411.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/simodoxil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=justice+league+snyder+cut+movie+online+freePDF 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_off0000b649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB649 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE60 11092 bytes
SHA-256: 0c34587d821210644ec04597010399fcb032a69ba579fea1b630ac2061030c1f
font_02_sfnt_off0000e81e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE81E 17508 bytes
SHA-256: bf94dbde16bd7c146b5e64f55fefe8ae526487cd98e126842a6f887140910fc7