Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4cbd5a029ca26e5…

MALICIOUS

PDF

84.6 KB Created: 2021-09-01 00:36:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a3fac76d1d83f7643dca6dbe234e4259 SHA-1: a4fe9eb64672978c0d1d26cdb963b422272b8521 SHA-256: f4cbd5a029ca26e56a3314ff8c064460807913adf8cecb091087b65607400039
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' suggests it may be used to trick users into downloading password-protected archives, a common tactic to bypass gateway security.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/480cce654d7b7678fc5d1222fa4db117/98066163866.pdf In PDF document text
    • http://artside.org/data/temp/file/94732740919.pdfIn PDF document text
    • http://cen7dias.es/userfiles/files/34837097122.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c26d8b9b80---86065188551.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b7c179b24---45016792432.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop//contents/87245260271.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/b6fa1da52327335305723097f0f2da87/kefagumapikalufova.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/12206191107.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/d0e66d65fa881bd42b8c5d6ef7f7c7b2/49069635430.pdfIn PDF document text
    • http://julianina.dk/upload/file/kufeposujab.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/lokusixinidulibako.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160909edc2e3ac---4708772170.pdfIn PDF document text
    • http://brainbond.ro/userfiles/file/xasavolukimojekad.pdfIn PDF document text
    • http://shesob.com/file/files/pazagovamowosamax.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608550c325029---jivotu.pdfIn PDF document text
    • https://atphp.ch/userfiles/file/wupexofapuri.pdfIn PDF document text
    • https://tekartltd.com/upload/files/kifowudij.pdfIn PDF document text
    • http://dietetyka-24.pl/images/files/61515745124.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-29/20210429115756216608.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/7f938c5af9a9fc5296ffd82e1a0d04b2/9092079336.pdfIn PDF document text
    • https://kawanmto.net/contents//files/64463172310.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/vafidumiposuvusegipo.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079b7dde66ef---6086298888.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/letimufagenezixifukup.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf2f085af6---55259664206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=james+w+nilsson+electric+circuits+solutions+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_off0000dc87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC87 10956 bytes
SHA-256: 49be53e389901011ebdde23f30228c606adcee2a71994987139c64b0acca5815
font_01_sfnt_off0000f5f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F5 21292 bytes
SHA-256: 612fbbb800feb900aa29bae4e90a5158f1dbed2e28a71d08199ea3e09ae7d144
font_02_sfnt_off00012c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1