Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1ef8b1b53e1706b…

MALICIOUS

PDF

82.9 KB Created: 2021-09-05 07:31:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b40111faa27411b8440c783650b373e3 SHA-1: 0c84a6531485acc56a7688f8be43525adcc90c98 SHA-256: d1ef8b1b53e1706b9cdc436072d9bf153ae8c8b15860a65aad27f629463c42ab
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://synerhu.ru/uplcv?utm_term=the+socionomic+theory+of+finance+prechter+pdf PDF link annotation
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b55c83e3150---79058660964.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161343f7a5adc3---37390228391.pdfIn PDF document text
    • http://toicodonlyson.com/uploads/files/zenorezamuwazuxurer.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/ibj3qq6v9d6opfev9khiejnek6/popatatuwirerimeg.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/53510270208.pdfIn PDF document text
    • https://bimetoor.com/basefile/bimetoorir/files/bozafaxupusejixixepojebek.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081aa17c5760---jinejawulavalokajevivi.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c41f7511010---6626804063.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/afbc8864a673336794cb1257a5d5569f/sebotatadojelovevuxudabos.pdfIn PDF document text
    • http://youil.org/userData/board/file/tizudo.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/nakabirefaremof.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/jewukesilafefosaf.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b1189a7be0---bigabuwabebovinokakugi.pdfIn PDF document text
    • http://health-bridge.in/upload/file/10412742866.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/dasenakobolafegekulemifir.pdfIn PDF document text
    • http://originalavto.ru/userfiles/file/zebatutesotujidojulu.pdfIn PDF document text
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/xuluvav.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/rewusodej.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/ief5a8kaa3a752d9svq36p0i6a/mupavewabubobuwu.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fcd98c59f4---pirixewalupevamis.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/a3ab2990e6c43709181defc6db2e41d1/31282039236.pdfIn PDF document text
    • http://www.kevimotor-rock.hu/files/files/namufogawudija.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/61234d9607866.pdfIn PDF document text
    • https://hefcom-hydraulics.com/ckfinder/userfiles/files/83301915759.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/56033052051.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/linamitinujikemu.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a67a746d88---20414508229.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/e5164ae9d85f4e83b793edcf3027bc6f/37608751498.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_off0000df5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF775 10916 bytes
SHA-256: cbc4b3542130daf4eae743482b952ccf02dee6032033338ccd4f01e55368dd64
font_02_sfnt_off00011096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11096 17464 bytes
SHA-256: 61536e1b5e8b9ff2ade01519053158e5fb9eb2163369eca653559bd0cf3b9e07