Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cdef3ea708219df…

MALICIOUS

PDF

70.8 KB Created: 2021-10-03 22:04:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 20a35a3e2652cd535774fe81f30af651 SHA-1: 1fc0f3437fd872ca6ab8d118ef1cfb46c102982d SHA-256: 1cdef3ea708219dfed490144b20ca2939552b2be5effafd504e58c5802b55e49
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is often used to exploit vulnerabilities or redirect users to malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the high number of extracted URLs, many pointing to disposable domains, suggest an attempt to obscure the true malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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.
  • 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://unicorn.mn/js/ckfinder/userfiles/files/fokopatudituzubutatojunu.pdf In PDF document text
    • http://stavclearing.ru/upload/files/koromumedabefuwoxifopip.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/12807462354.pdfIn PDF document text
    • https://mancomunidadvaldizarbe.com/userfiles/files/surasupigemopege.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/suzekabigerorikowi.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/8684980605.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/16736812210.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/jlut8604virft3427kcc0jeret/66255730042.pdfIn PDF document text
    • http://builderall.info/userfiles/file/bugeliwo.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396aae1b4b4---sapiwanipaj.pdfIn PDF document text
    • https://intrastorg.com/userfiles/file/zebudejikerosewif.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/54328186265.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/dimifujixinexubijupu.pdfIn PDF document text
    • https://robertbah.si/files/file/46123963052.pdfIn PDF document text
    • http://vswet.ru/f/mabikejogusizaji.pdfIn PDF document text
    • http://goodfortune.hk/UpLoadFile/file///31818794152.pdfIn PDF document text
    • http://www.heatandgas.com/EditorImages/file/zugosarasiwikusomaguvese.pdfIn PDF document text
    • http://jadeite.ru/images/file/35092741152.pdfIn PDF document text
    • http://geojeoceanhotel.com/userfiles/file/20210905075546.pdfIn PDF document text
    • http://stavebnevyrobky.sk/www/upload/files/zekimufotuzuxeme.pdfIn PDF document text
    • http://canxetaianhduc.com/images/file/kujewagiduvutugolidurot.pdfIn PDF document text
    • http://canyonoaksmtg.com/~duckdi5/canyonoaksmtg.com/content/file/wemagilolenukalerukod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=2008+can+am+spyder+owners+manual+pdfPDF 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_off0000b109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB109 11244 bytes
SHA-256: cde89597ca5333c9c0b276a9c471afa2e7505079eecf63a7eee382fd25946867
font_01_sfnt_off0000cb8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e39c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE39C 15828 bytes
SHA-256: 9f63c84df365e77b2091b5abe458628d42ce147894c35ff7c18273e6a531407d