Malicious PDF — malware analysis report

Static analysis result for SHA-256 fca52cb41da1004e…

MALICIOUS

PDF

81.8 KB Created: 2021-09-18 17:32:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 71242d1f3965f3fca11f411d4113a62f SHA-1: 53de26e594eebad9b418d2b8ef11419192ca1ac9 SHA-256: fca52cb41da1004e98e666cf47b99998c4a318861e377cf2bb50b08a5122033a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript and a large number of external links, many of which point to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution campaign. The presence of embedded JavaScript indicates an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://irlanc.ru/uplcv?utm_term=download+video+by+url+android PDF link annotation
    • http://barrospizzadb.com/uploads/files/koboxugejasa.pdfIn PDF document text
    • http://kazuma.ru/ckfinder/userfiles/files/6147519497.pdfIn PDF document text
    • https://defi128.com/userfiles/files/wofuvegekijikiwexebab.pdfIn PDF document text
    • http://cuacuonnhaxuongbinhduong.com/upload/files/84085066920.pdfIn PDF document text
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/1432770090.pdfIn PDF document text
    • http://longarmquiltingacadamy.com/fckeditor/userfiles/file/pufimor.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/7513121180.pdfIn PDF document text
    • https://jiu-hang.com/upfiles/editor/files/57927560412.pdfIn PDF document text
    • https://bodzlomu.com/userfiles/file/60254990662.pdfIn PDF document text
    • https://vilus.cz/userfiles/file/gojokifabixum.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/58q60suhseg5cc1du3d0197k1g/35026316625.pdfIn PDF document text
    • http://exosushi.com/uploads/files/terudufunivom.pdfIn PDF document text
    • http://lagrupacio.cat/file/ruvawoloniwigerekad.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/5e49c28d30c1b2bb2d57ad211044a127/vigojosixubas.pdfIn PDF document text
    • http://ukrkarta.ua/fckeditor/userfiles/file/vivijomewid.pdfIn PDF document text
    • http://technoauto.jp/js/upload/files/29196508885.pdfIn PDF document text
    • http://studiogiamberardino.it/userfiles/files/92088126275.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/551087889.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/5516601688.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/72d3540979ac84575606596237a1e7ae/jolebuwefifavukilodel.pdfIn PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/89239929333.pdfIn PDF document text
    • https://ksi-system.pl/editorfiles/file/wudabejulariwoxegefon.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/kulojufi.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/28373194494.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_off0000dda3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5BA 10484 bytes
SHA-256: 7ef2995cfe48aeeee6bd324692497650ffd6047e6e3ae5e1668cb83e646c6091
font_02_sfnt_off00010d99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D99 17044 bytes
SHA-256: 95c7aa183a97dd2b5d52e54a29c2120b193398ad2413aae19efd808f2bd46fb2