Malicious PDF — malware analysis report

Static analysis result for SHA-256 43c754d29c0b4140…

MALICIOUS

PDF

82.8 KB Created: 2021-09-16 16:35:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4dd83d8d5802d62c8937640469d8c3b5 SHA-1: 6e019b6ad82d95744889cca54b1786723733a3d4 SHA-256: 43c754d29c0b4140f464a00cdfeacf5d646796f2f4fef70905e4a425ed86ab0d
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external files, many hosted on what appear to be compromised CMS upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of multiple PDF link farms suggests an attempt to obscure the true destination or distribute various lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://utcsp2.rustyramone.com/uploads/files/xuvadage.pdf In PDF document text
    • https://stormester.no/files/file/22083438149.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16135e3d32f7e1---83541871891.pdfIn PDF document text
    • http://smelawservice.com/file_media/file_image/file/witikibuxanana.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/6a711f7e1ca654d33e363c8a6901ff8c/zavixifegirugozisat.pdfIn PDF document text
    • https://tckontrola.hr/files/10524650744.pdfIn PDF document text
    • http://ilsungwarehouse.com/userData/ebizro_board/file/xituzinemojipurevegonevo.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/67f513c73ac1658e6aca438c22355f27/fididavika.pdfIn PDF document text
    • http://jnejendomsdrift.dk/userfiles/file/dezugufosalakiz.pdfIn PDF document text
    • https://10s317.com/uploads/files/202109090846267343.pdfIn PDF document text
    • http://giteduguedesboires.com/userfiles/file/69043184713.pdfIn PDF document text
    • http://vietsonplastic.com/uploads/userfiles/file/magesavivojuveli.pdfIn PDF document text
    • http://greenhousehotel.vn/uploads/image/files/32130594614.pdfIn PDF document text
    • http://saraya-shop.ru/upload/files/fetudotefewajutadem.pdfIn PDF document text
    • https://stw-nowogard.pl/download/file/77390263920.pdfIn PDF document text
    • http://agierresrl.it/userfiles/files/7174899941.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/pibasi.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210911162422.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/19487274323.pdfIn PDF document text
    • http://fkm-lux.by/var/upload/file/rotabukiwuxakixotus.pdfIn PDF document text
    • https://apra.pl/files/file/wemawazumisokefevimejibad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=pubg+game+logo+maker+online+freePDF 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_off0000df4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4E 10624 bytes
SHA-256: 472e3453b457df991f9d599b160c4121199fb49677354e5a7d3c9a4c6c161d7a
font_01_sfnt_off0000f780.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF780 17716 bytes
SHA-256: b0ef83f55c30d8940a01984ff8809b5714ea6a577dc866a10718c335e08ecc03
font_02_sfnt_off000125bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1