Malicious PDF — malware analysis report

Static analysis result for SHA-256 4535b619a96d8e53…

MALICIOUS

PDF

88.5 KB Created: 2021-08-08 01:00:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4197c581b5fd61c07cf798de6b62225e SHA-1: a21d16517c235a53913224fbb6f3366e6099e6a3 SHA-256: 4535b619a96d8e53871908807e5714ecc385cb9526ae8f8b73ee7c538ac78afd
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable domains, likely to lure users into downloading further malicious content or visiting phishing pages. The embedded URLs and the heuristic firings strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • 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://garglob.ru/uplcv?utm_term=exercices+imp%C3%A9ratif+fle+pdf PDF link annotation
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1fdf3f317---gebawalizazafonodixowuju.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/e2a42491dafc6162769d0c52795c7546/semaxumaresofomobuji.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/2494722e4da7d16d70fc381ab2114f80/fasakubalo.pdfIn PDF document text
    • http://say-international.eu/userfiles/file/7063809267.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/43192530371.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d61242aa27f---27048373655.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a607e61aaeb---teliminukidikopiv.pdfIn PDF document text
    • http://capital96.com/userfiles/file/15212189538.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/533c8e04620cae7fed8149d6823f9268/5341550491.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/raxunimanojepifutagavu.pdfIn PDF document text
    • https://keongracun.org/contents//files/bilasudenamuzipekolerivi.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/sififufuxazaleji.pdfIn PDF document text
    • http://weddingdiy.cc/uploadfiles/files/20210618_231722_2863.pdfIn PDF document text
    • https://fontaine-eva.fr/userfiles/files/mudaduvonozinurewat.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///naxajoto.pdfIn PDF document text
    • https://jxloanchien.com/style/postimage/file/48288717795.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/rawegod.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940bbba3f15---wolonutidoduxobogulog.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/ed450e4e214bdd5769827f38e878a678/75244881707.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/9609087720.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089ccc3a4bfd---dapesejasupodivuvapofubam.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086458a33579---50051035284.pdfIn PDF document text
    • https://f27szerviz.hu/upload/files/luziriwosixawanig.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1606e280927e4d---jimefopekalagalewabotud.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/98947684161.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/13351375880.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://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_off0000f069.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF069 19324 bytes
SHA-256: 81e863f9c3e52e221223456f1d9e980455b73b6d2cd3d3dcc52030cb0d95d9ae
font_01_sfnt_off00012150.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12150 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13967 10796 bytes
SHA-256: 6a4720a15bf55b64235695ea94bbacb0503e93148766da825b049bbfc62bc326