Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ca34dc920497d78…

MALICIOUS

PDF

73.5 KB Created: 2021-09-18 02:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9df84abf877593ca84c4e5b070352af SHA-1: 1852deca8848a78429a76886cdbccc92bac6136c SHA-256: 4ca34dc920497d78625e4c100f45f6824fb7753c092edbf0fa1f019fba994df9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were directly extracted, the PDF structure and link farm heuristics point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://powermailer.in/userfiles/file/62890405050.pdf
    • http://infrabud.eu/fckpliki/file/pigekirikerivolomoxoxam.pdf
    • http://webinaris.blog/ckfinder/userfiles/publics/files/vekomupedovitoworalewurug.pdf
    • https://brs.jo/userfiles/files/lofuwagerisawakonomu.pdf
    • http://youil.org/userData/board/file/rotazesix.pdf
    • http://recko.ru/ckfinder/userfiles/files/31038140103.pdf
    • https://peisheng.org/uploads/ckfiles/files/613f92a1b5b32.pdf
    • https://silverbirdmarketing.com/pages/images/file/38935404786.pdf
    • http://kitpaisal.com/mypicture/file/kazefurufigapuvu.pdf
    • http://reckdance.pl/userfiles/file/newona.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/b55202719d141072906e2af66e56947a/figiwijigotelaturerapu.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/3638aa981367d0db829f1ae2ae4009c3/dotizuxuzoduwijubir.pdf
    • https://suncables.co/images/file/3968911021.pdf
    • https://bestcoloringpages.com/userfiles/file/kuvunoxegilobuzarowusip.pdf
    • http://oilspecchem.com/files/gasuralemesixufofanoga.pdf
    • https://jmtours.co/aym_image/files/tazekifar.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1614167eaafe90---54919965270.pdf
    • http://cabini.it/userfiles/files/78057258513.pdf
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16142233e05c30---jinovimu.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dbeea99e62---71976151315.pdf
    • http://gestaocipa.com/public_html/Imagens/file/jumobutamuzurufupuvarosis.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=vpn+secure+ios
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bd9b.bin
3c09a3fdec118fd0a2e82fd344756c6db76cb0d4bb64c967e29cc03d700a0fb2
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD9B 10132 bytes
font_01_sfnt_off0000d458.bin
8f58da86d22fde2d58e184812ed5aea3e14a1283cfbd59631daa5a87c061283b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD458 17224 bytes
font_02_sfnt_off000100ab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100AB 16792 bytes