Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab608febb87ba304…

MALICIOUS

PDF

69.5 KB Created: 2021-09-10 13:28:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a4caa3d18be4366aabab7e0e04da3f36 SHA-1: 3d39946a94a8a85162bcad417605f27ce1dcb179 SHA-256: ab608febb87ba3045a19dabc14b89224484d82e308c73943fa37e84e160ba549
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous links pointing to external domains, some of which are hosted on compromised WordPress sites or appear to be disposable. The primary purpose seems to be directing users to other potentially malicious PDF files hosted on these domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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.
  • 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://angkalaris.com/contents/files/50044673365.pdf In PDF document text
    • https://sankaibearing.com/userfiles/files/78403489101.pdfIn PDF document text
    • http://universalgroupautos.com/files/others/91706558413.pdfIn PDF document text
    • https://nusamulticentralestari.com/Uploads/userfiles/files/79615613036.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/zagunobugadokumipinoliv.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/jawipiwagonujajopi.pdfIn PDF document text
    • https://bongkartuantakur.com/contents/files/96267344297.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/xulidef.pdfIn PDF document text
    • http://churchontherockuk.org/home/churchontherock1/public_html/userfiles/files/nixivavi.pdfIn PDF document text
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/vukarefotulunudedapedojuv.pdfIn PDF document text
    • http://athaj2.specialty-match.com/upload/files/zezinud.pdfIn PDF document text
    • https://ibericadearmerias.com/file/tixofofa.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16139137a601ee---41675265493.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/96417146915.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/legowasojaxigexab.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16130c1cdadd23---nefotamanepobetudajufuk.pdfIn PDF document text
    • https://artenika.pl/fck/file/budexutoxevasal.pdfIn PDF document text
    • http://ashokarefrigeration.com/userfiles/file/dudigujiwadumawusopiw.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/c07eb5b44407f4f084a9ca947c92e35a/37160878487.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/42569055555.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/84921089082.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/bf6f693f87b68bd19bd2351c7163fe2c/53140711111.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1df729d28---54464293190.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=subway+surfer+mod+versionPDF 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_off0000b091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB091 15764 bytes
SHA-256: c600847c425ac063c5af8a3295c83baba57e4e409617b32ff505b6e714923210
font_01_sfnt_off0000d724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD724 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3B 10952 bytes
SHA-256: 067b012ada7a5362fc4ed6c587ec41b61e5c4772cec6ccf68a1849d0313f6baf