Malicious PDF — malware analysis report

Static analysis result for SHA-256 c236edc23405418f…

MALICIOUS

PDF

82.6 KB Created: 2021-09-02 01:08:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dd6fb4c86459a51adc755eea9e319ccd SHA-1: dfe08f21a2b6383a9045dc4168ff6d27332fab20 SHA-256: c236edc23405418f2226850698397e5004dd18fd6840fadbee484215cf793925
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content or phishing pages. The presence of embedded URLs and the overall structure point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://inwebjor.ru/uplcv?utm_term=complete+reference+java+pdf+free+download+7th+edition PDF link annotation
    • http://cityhelps.org/clients/6/61/61afa7a028a8e04f14432b0fece6f2b0/File/95920795317.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db696c38c9c---31131064335.pdfIn PDF document text
    • https://teenvolunteerhouston.com/wp-content/plugins/super-forms/uploads/php/files/7c3d347875d9f3c0daf60f75c9657945/doxanawefaruwamelop.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/wokevenivojex.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/megil.pdfIn PDF document text
    • http://hrt-foto.hu/_user/file/sufubujujikaruniziwuv.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/rolejomotesizuzodu.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/tonepesonejar.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/679adfa7a1546dd43a4ffb1dd7a2d257/2036569268.pdfIn PDF document text
    • http://flapboxes.custompackageboxes.com/userfiles/files/koxiwuvone.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/70783670211.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160eca847a6df4---51447137344.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210815183107094.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160b246fa87a6a---pupurujagila.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9cf4f75c8a---guvunumo.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/97694032300.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/puwavonofos.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/15888193978.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098352a82d64---93225334574.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/bk84jl337pdselnt393bvf7uf3/4931974120.pdfIn PDF document text
    • http://csc-0898.com/userfiles/file/20210713210009_knwhps.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607294a1a30e1---wenepulud.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/juruvudagusisovigabubap.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/ziked.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/81343169135.pdfIn PDF document text
    • http://jiangsutravel.kr/userfiles/files/20210706_153413.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_off0000dd25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD25 17172 bytes
SHA-256: b655eaf1961e981e54dc7980ebfeaa43cbb1a3893088516ee52e18761c97f12c
font_01_sfnt_off000109aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AA 11080 bytes
SHA-256: 8409524f58db5b4fe10dc053451a2610d98c5b0511a78da62a565449b238b6d0
font_02_sfnt_off0001235a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1