Malicious PDF — malware analysis report

Static analysis result for SHA-256 a00fbfee29cf055c…

MALICIOUS

PDF

81.0 KB Created: 2021-09-22 10:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3547a7668272d4b0946f837208091cae SHA-1: 3573b70ebff7ae8ddaa75360386a309cdd9cd83f SHA-256: a00fbfee29cf055c9acfe27ad9e9c1373f457f567b9ddfdf06bb51c1cbccb51f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by multiple heuristics and ML classifiers, including ClamAV. It contains numerous external URLs, many of which point to compromised CMS upload directories or are part of link farms on disposable hosting. The PDF structure and embedded URLs suggest it is designed to redirect users to potentially malicious websites, likely for phishing or to download further payloads. No scripts were extracted, but the PDF's nature strongly indicates it's a delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://crewmak.ru/uplcv?utm_term=the+crowded+room+watch+online
    • https://worldmedglobal.com/userfiles/files/56306447137.pdf
    • http://marmaraisg.com/images_upload/files/fojapugude.pdf
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/ac6edf1c2a4a5546a59c24d779b25a1b/23483323330.pdf
    • https://altonika.pro/files/fck/file/65246850388.pdf
    • http://erictex.com/ufiles/files/43334735384.pdf
    • http://pphjako.pl/userfiles/file/tumotozijolatudelijupaf.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a401aac6e9---15545144213.pdf
    • https://ddnepal.com/assets/userfiles/files/vozaxinexogafisizojisu.pdf
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/64755072408.pdf
    • https://readandenjoy.ae/userfiles/files/92671895686.pdf
    • https://ladangmimpi2.com/contents/files/nujomudukuzivajev.pdf
    • http://showplus.ae/userfiles/files/tapuwinonoturuse.pdf
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/75346510560.pdf
    • http://1night2day.com/ckupload/files/81304810968.pdf
    • https://bipalisdemo.dashindonesia.com/userfiles/files/71514845622.pdf
    • https://artgallery.devctn.com/ckfinder/userfiles/files/58256737515.pdf
    • http://musthighschool.mn/ckfinder/userfiles/files/33446576546.pdf
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/4aa41d779ec1fc243932f55350a1ca2a/48680103639.pdf
    • http://hocikto.info/userfiles/file/mijedupogugafag.pdf
    • http://sayarbobinaj.com/file/pateved.pdf
    • http://smartdeal.pl/files/upload/files/96465283489.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4b613c569---48805490491.pdf
    • 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_off0000d882.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD882 16792 bytes
font_01_sfnt_off0000f099.bin
e966823ed9aeb731211fb832e7ec3b12edd6b2fb5f8a2ca8134fd261f96566ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xF099 10516 bytes
font_02_sfnt_off00010860.bin
c4a38618bb60779ea7ab6d918adc7f7e372261cf6c38015125f2c1bf87c909de
pdf-font-stream PDF embedded font (sfnt) at offset 0x10860 17844 bytes