Malicious PDF — malware analysis report

Static analysis result for SHA-256 49bfb38452c4df5f…

MALICIOUS

PDF

81.8 KB Created: 2021-09-16 19:27:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5cac66f078c5922583049d89d6bcf4c4 SHA-1: 6f768e03c862b3bc80b73685be03983055d169e0 SHA-256: 49bfb38452c4df5f848bf664f64f473c8f7e6a66d2ac66dbc5e607f6fee08812
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to obscure the final malicious destination. ClamAV detection and ML classification strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 7

  • 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.
  • 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://infrive.ru/uplcv?utm_term=merge+duplicate+contacts+on+android PDF link annotation
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16135957ab2bbc---vovuzoz.pdfIn PDF document text
    • https://fleuriste79.fr/ckfinder/userfiles/files/rarejinezafedagibobave.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/92971730714.pdfIn PDF document text
    • http://www.aaar.cat/assets/js/ckfinder/userfiles/files/ziketelev.pdfIn PDF document text
    • https://commonwealthsportsawards.com/userfiles/file/buvig.pdfIn PDF document text
    • http://grandfiltr.com/files/file/xigijikelotufeviwoz.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/72ejbr2gcfavap90g03fjml75l/kafawirowujame.pdfIn PDF document text
    • https://homestayhoian.vn/uploads/image/files/vokusibanom.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/33487887555.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/laluj.pdfIn PDF document text
    • https://jjpremiers.com/files/78744271702.pdfIn PDF document text
    • https://anakmeong.com/contents/files/naguzavujajel.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/tasobufafimakaviw.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/942fcbcd56497a165bad75a861c4658b/88736008490.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/be1449e13a9a5bd263ef3ecafb7feebd/noxipobu.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/mlhkefg8m999ev92f5lqfhf03n/17937508377.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/76895421058.pdfIn PDF document text
    • https://kentacademymiango.com/userfiles/file/40200731166.pdfIn PDF document text
    • https://cqhuaan.myhost360.cn/upload/files/09-01-07-37-54-95.pdfIn PDF document text
    • https://fundoohairstyles.com/hairstyler/images/file/88377412395.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://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_off0000dd48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD48 10780 bytes
SHA-256: 836741016967e5300915ce842e86ef2601971c3a446e2370a341477e5e481209
font_01_sfnt_off0000f5ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FF 19288 bytes
SHA-256: 84acd6a5e68d02739f6b5f86db27c3def965be6aafdc617e4754ba85b5066e0e
font_02_sfnt_off000127ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1