Malicious PDF — malware analysis report

Static analysis result for SHA-256 a938dec32eba4601…

MALICIOUS

PDF

81.0 KB Created: 2021-09-08 17:11:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 30ca655dec8c92aa8c46890ab70c16fb SHA-1: 1daca2df79c3373b5e9a526eca59cc2063e9f60a SHA-256: a938dec32eba4601ac3a6691869246e05e2581ef180cd1478d2456637a37fdf2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to numerous other PDF files hosted on compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the structure and URL patterns are consistent with a spearphishing attachment used to lure victims to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://pikhospital.com/ck_uploads/uploads/files/keliluwatigumufotukal.pdf In PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/jazozowesevevubilu.pdfIn PDF document text
    • http://kliknetezde.cz/admin/obrazky/file/38234818442.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/45878694703.pdfIn PDF document text
    • http://enovosti.info/ckfinder/userfiles/files/vojekonezufukarozorutenof.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/lugopoluvaruxipiroxazaf.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/qtp5kjlotpa00nreg9kdg2kl4s/xagep.pdfIn PDF document text
    • http://lianbang123.com/uploads/files/202109041724264454.pdfIn PDF document text
    • http://355353.ru/userfiles/file/13876149609.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/fefodagupelito.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/spt4avvvqjs5tee9uecgvr2mbk/71842107921.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/kexanufobokabagotikagabak.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109031838293951.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/navegekabuniwekig.pdfIn PDF document text
    • http://kastely-vacduka.hu/fileok/file/27969102122.pdfIn PDF document text
    • https://booking-news.hkdnracing.com/webroot/editor-uploads/files/14606396748.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/5089399393.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/75105331268.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/fudajuwufalibujutid.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/57136085452.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/vodupenufaf.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/94457fd40cc90d31b9a9983944430784/77225779148.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=positive+and+negative+coterminal+angles+worksheet+answersPDF 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_off0000d450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD450 11064 bytes
SHA-256: af592ecba34c2b2427868f7de369008f25412714bbcbd628d60f00eb7f3893a6
font_01_sfnt_off0000edc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC4 18516 bytes
SHA-256: e8aacd28d21cee0926b8b122342bbc85649f6e591e6f92cd24fcf5b6b309cfe7
font_02_sfnt_off00011dbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1