Malicious PDF — malware analysis report

Static analysis result for SHA-256 71bf2a23f3ad712c…

MALICIOUS

PDF

74.6 KB Created: 2021-09-13 19:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 719393f64185c0c3280d0777070d94b5 SHA-1: 2571aecadc77b66b7331301e9bad04f9868b5234 SHA-256: 71bf2a23f3ad712c828f864c090125884c336b77e703959887cfe146c02f7e9d
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which appear to be compromised CMS uploads or disposable hosting. The primary purpose seems to be directing users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://digireg.li/upload/nopabamaw.pdf In PDF document text
    • https://bloomeng.com/uploads/famusesir.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/xugiv.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/lejilaferakadevazuligate.pdfIn PDF document text
    • https://f2h63c2.ip4secure.net/upload/files/narafelisitamupezesowag.pdfIn PDF document text
    • https://dcimx.com/files/3663860485.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342d13988bc---pawuziduloxijabojevanomej.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/44133484552.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/4386840331.pdfIn PDF document text
    • http://urgentcarepb.com/userfiles/file/83633250297.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/85426294943.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/efec2788724deea7d5869415a5d8cd72/51525489984.pdfIn PDF document text
    • http://tekizolasyon.com/ckfinder/userfiles/files/51392859915.pdfIn PDF document text
    • http://vetranhtuong.info/luutru/files/tetebawifulewix.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134f71f512c3---zenuzikenilozofesorujetep.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/rerinoxalatumukewasefuv.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/goboporadosi.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/94984967689.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/26203610593.pdfIn PDF document text
    • http://sbkf.org/files/files/jisulidinafubufuxa.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/58908552569.pdfIn PDF document text
    • https://schachverein-marchhoefe.ch/fcsr/news/upload/file/92216409569.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=free+bc+hackPDF 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_off0000c1bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CE 17628 bytes
SHA-256: 4bad8cee81591efe91225cc42380e67b81afbf0c7ce58a88f20313d4ef8a5aa9
font_02_sfnt_off00010754.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10754 9908 bytes
SHA-256: 8ca51b8f320b7b7103a5f3f443eacfe4b97ae3c893be9e2c80cd99e6c5861d4b