Malicious PDF — malware analysis report

Static analysis result for SHA-256 9893b789b5388a97…

MALICIOUS

PDF

73.9 KB Created: 2021-09-26 19:16:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3cdc7e3d8fad5941760bffd01e16e078 SHA-1: 4ad42deed0fd32bf8834d39bb0113a25e4fb6555 SHA-256: 9893b789b5388a97d00891f4a7cf70a125a823481a5a39904a1732c55fff02bb
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution lure. The PDF structure and embedded links are indicative of an attempt to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://4226080.kad.tw/kads/ckfinder/userfiles/files/wijufuvizibululariwitabaz.pdf In PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/42c7e417553545056e24b0158df0750b/89600937535.pdfIn PDF document text
    • http://dentalcenterstudio.it/userfiles/files/75680772412.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/xakexolu.pdfIn PDF document text
    • http://nsk-nalogov.net/upload/files/kojofodud.pdfIn PDF document text
    • https://salonrewards.ca/images/file/legoza.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142f441ccbf7---xekuseloxexafukada.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc3fc5ce62---pazurufonumu.pdfIn PDF document text
    • http://aktifithalat.com/resimlerfiles/55008781201.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/95209792608.pdfIn PDF document text
    • https://topupdana.com/contents/files/zetubusejiwamubijulosake.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/topegixuwogazu.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/suzegadefaxodarep.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/tebiluserolefo.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210916_7FD343134369F37F.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/9634547627.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314aa6c9b7d---85237657093.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/xujowopixumom.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/0ce2d6b150f53c8244a60b820cd420c9/1455712185.pdfIn PDF document text
    • http://asesoriazabalburu.org/azaba/files/file/65353165763.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/923490751.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143d71c9a0b4---nejovefot.pdfIn PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/bisefibo.pdfIn PDF document text
    • https://inprovit.com/ckfinder/userfiles/files/83854985913.pdfIn PDF document text
    • http://sage-chem.com/image/files/20210913_085532.pdfIn PDF document text
    • http://portamarioarchitetto.eu/userfiles/files/sotugiwimirafalekisegolop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=unblocked+cookie+clickerPDF 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_off0000b97f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB97F 10172 bytes
SHA-256: 95ad944307e8316c546ff3e5026fb707281e697305d7852429e8f24133d57828
font_01_sfnt_off0000d046.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD046 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e858.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE858 19068 bytes
SHA-256: 876aa67da4333d6320ef4172cc6fcfd409ebcc8c8c3bdb12fc874acc2e9d888b