Malicious PDF — malware analysis report

Static analysis result for SHA-256 acafe08ed4c012d4…

MALICIOUS

PDF

73.4 KB Created: 2021-09-08 15:53:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 0dcadc1235c27605b5b1c8cb82d4d619 SHA-1: cce180608db91fc55d11f1f79b130be6629af46f SHA-256: acafe08ed4c012d4b43c201599db26932769a06e6903f34f1ab1659f4cfcf9eb
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier strongly indicates maliciousness, and the presence of JavaScript suggests it's used to facilitate the redirection to these malicious sites. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://queure.ru/uplcv?utm_term=dermatite+at%C3%B3pica+pediatria+pdf PDF link annotation
    • https://saikekanglun.com/filespath/files/20210907011011.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/nagekizikezasezufuwa.pdfIn PDF document text
    • http://solarissoft.com/img/userfiles/files/19548566090.pdfIn PDF document text
    • https://imad0c0.com/js/ckfinder/userfiles/files/labozepesidexuzub.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/25223728705.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/ed806a330d9256d636aa5d6ea6991670/14282215462.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/64144729636.pdfIn PDF document text
    • http://ttc-investco.com/img/files/votafakenululawu.pdfIn PDF document text
    • http://ad.ditroinfotech.com/laportal/ckeditor-ckfinder-integration/uploads/files/dejujilopelavaxapebik.pdfIn PDF document text
    • http://leprofit.ee/cmsfile/contentfiles/13064562400.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/rirevexivanazudaxobuw.pdfIn PDF document text
    • https://fototipia.hu/files/files/26587189625.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/161312c1877dd4---puwovagowe.pdfIn PDF document text
    • http://hexindechem.com/upload/files/51479655390.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/64860339322.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133f8db0c274---xorasasusugori.pdfIn PDF document text
    • http://chenruichem.com/upload/files/bamobomulixanufibu.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/12829128938.pdfIn PDF document text
    • http://taigesw.com/upload/files/jodevuxixojorubawo.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/94658037094.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/21111975506.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/40014403981.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_off0000ba79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA79 10484 bytes
SHA-256: 03101c5a9867617f6c483d1a42e6dd1fd4167a9c6e8a34915f6c64aca1c40814
font_01_sfnt_off0000d256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD256 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA68 18040 bytes
SHA-256: 0d444729fdda40d12ea5cf89513ac6a6c9558a251a0d235d87e54a32e606a6ad