Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2fdb25bf7d3b20f…

MALICIOUS

PDF

68.8 KB Created: 2021-09-28 23:31:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fb2111fcf706a21d35927ce7187534c2 SHA-1: e7eeb5c3e0070f7bcc42b3736143d9969429cce1 SHA-256: a2fdb25bf7d3b20fb3c17b9f352ce069bf0283b8009b136414ee7af1b713a06f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://smidgel.ru/uplcv?utm_term=how+to+empty+spam+folder+on+android PDF link annotation
    • http://teknis.it/userfiles/files/jaregobebib.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16141aac27ca7c---mabimunen.pdfIn PDF document text
    • http://dmychadla.eu/UserFiles/File/96678552339.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/161394de33714b---17750327030.pdfIn PDF document text
    • https://vleek.com/uploads/files/56100084042.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/ef60ef8273a06984ece7b91d370e0d6b/62142603499.pdfIn PDF document text
    • http://gdwtechnology.com/fckeditor/file/zezipi.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/gajid.pdfIn PDF document text
    • http://studiomanzetti.it/userfiles/files/10486435092.pdfIn PDF document text
    • http://ccshecea.org/upload/files/69507844249.pdfIn PDF document text
    • http://balatonfurediallatorvos.hu/userfiles/file/59903108500.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/85473341155.pdfIn PDF document text
    • https://fivetc.net/uploads/files/94108188776.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/33500964747.pdfIn PDF document text
    • http://nhadatv.com/webroot/img/files/xelifixazosumibaregasama.pdfIn PDF document text
    • http://roleco.pl/data/aktualnosci_imgs/file/33310084882.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16152debbd2a57---novexebafofax.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c11a783601---53207420745.pdfIn PDF document text
    • http://www.siphonicflowmandiri.com/upload/files/zobanufufilotafe.pdfIn PDF document text
    • http://ametansk.ru/uploads2/66198415294.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/557454a66cf20349ba6629c37f21dca1/lupor.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/fodulabug.pdfIn PDF document text
    • http://maihome.hu/admin1/file/65013203847.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_off0000afef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFEF 14572 bytes
SHA-256: 975c16d0918337b7a24231a6c3dd4a7add5a29c9204ca81959312eb8f9388f97
font_01_sfnt_off0000d43b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC52 10852 bytes
SHA-256: ebe6cbab77dcab760a46456e2fd24bddd3399721df6f45fbc87036b88984eab5