Malicious PDF — malware analysis report

Static analysis result for SHA-256 5100b71afe0e7933…

MALICIOUS

PDF

71.1 KB Created: 2021-09-13 03:06:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: cd51d10c5fba095c5f1ab813fa24351b SHA-1: 7fc956881b3b8dd5bbe5b20818e2bec5d8bec64e SHA-256: 5100b71afe0e79338d117ce85e6938c124908063aed3737465c2ae326eda66fa
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness, with ClamAV identifying it as a phishing trojan. The PDF contains numerous external links, many pointing to disposable domains, suggesting a link farm or phishing lure. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://noddy.nu/images/file/jabezelenawuvukebifi.pdf In PDF document text
    • http://xn--or3bo5mvlb.com/data/editor/file/33444818504.pdfIn PDF document text
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/97129681046.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/66061950660.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/vujuni.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/jalonekikogokiwudolow.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/4700454370.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/49469498552.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/96657856125.pdfIn PDF document text
    • https://isosklo.cz/uploads/mapudobos.pdfIn PDF document text
    • http://lesmashclub.com/imgUpload/files/34258066503.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/85342672120.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/pazogewesita.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/jonisolofixunolizazazisig.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/kuraditavasizofejuli.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/tijavokusorejukutow.pdfIn PDF document text
    • http://olympusflights.com/files/files/40962072738.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/6501941348.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303f951a171---mubetajafizupe.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/texaduloju.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/57493773018.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/59232700707.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109081054046522.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/28435499632.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/lizoxilopirazadu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=hd+nature+wallpaper+download+for+androidPDF 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_off0000b680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB680 10500 bytes
SHA-256: ea6c8ac5392fc224ded81413d44953958c2b2edc77ead6d3d91e77e14effaea6
font_01_sfnt_off0000ce6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6C 15776 bytes
SHA-256: 225305f749e229bdea4b373119af441c5e69d2df113827cb59a8461732316f0d
font_02_sfnt_off0000f64f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1