Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc533e5e55c545ca…

MALICIOUS

PDF

85.2 KB Created: 2021-10-09 01:01:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 05fa43749578587c6ba4c6c460594af0 SHA-1: efebd89e22063f77fd72d65747f75ba3a9469b18 SHA-256: fc533e5e55c545cabdc9774cb13577db307e354d61803d2cabed7f9b24f8b57a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://allytemp.ru/uplcv?utm_term=formwork+for+beams+columns+and+slabs+pdf PDF link annotation
    • http://sochisushi.nl/survey/userfiles/files/nafasesinenomogito.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d4d2bdccb1---nikatuvekebedusexode.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/rudufe.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161322e2e3d028---pebux.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161302cc479871---24010071459.pdfIn PDF document text
    • http://law885995.com/upload/fckimages/file/11524577268.pdfIn PDF document text
    • http://chronocertif.com/userfiles/file/zerenivakulejes.pdfIn PDF document text
    • http://top1np.com/ckfinder/userfiles/files/woxesaxoduka.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/jedepodigedudisumubo.pdfIn PDF document text
    • http://newmob.it/userfiles/files/91995231623.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/b4cb6afc0bcd415a6e1dffde0f15f2cf/10242800159.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/zagapufo.pdfIn PDF document text
    • https://hanomanberjaya.com/contents/files/1410575790.pdfIn PDF document text
    • http://hosungtour.net/FileData/ckfinder/files/20211006_2C9F2AAC48156398.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/91916668229.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/zoxoruxumapigeganokiva.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/86715520400.pdfIn PDF document text
    • http://sergeybazarov.ru/file/wulaxikowoxa.pdfIn PDF document text
    • https://ozsersogutma.com/upload/files/39293994248.pdfIn PDF document text
    • http://uchid.com/uploads/file/29532433046.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/mafoxapenuledetalitaruke.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/fateked.pdfIn PDF document text
    • https://www.anoregmt.org.br/ckeditor/ckfinder/userfiles/files/towiwijulofogagu.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_off0000e04c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE04C 20940 bytes
SHA-256: 60d0170600ac528cd0ae6fceee13151ad87204696829afbd163f7cf40edd85c8
font_01_sfnt_off000115bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115BF 10984 bytes
SHA-256: 89d20442a3e664508732f828e2bb2a7b0273c4c83ee8bbf98f5ca08e253a546c
font_02_sfnt_off00012f13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1