Malicious PDF — malware analysis report

Static analysis result for SHA-256 1316214c02785c53…

MALICIOUS

PDF

88.4 KB Created: 2021-09-06 03:07:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7db28ce5c7ce9e5d33e64ed676bccfb8 SHA-1: ab516b48c3c184f1cf3f10114ab7bd1537a61210 SHA-256: 1316214c02785c5351a0b04375f6201403871af4735281ab3b53c6cba762c4ff
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier and ClamAV, detecting it as a phishing trojan. It functions as a link farm, directing users to multiple domains, some of which are hosted on compromised CMS uploads or disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for human readability but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://harryfok.com/ckfinder/userfiles/files/femesumulagupunoxigumitib.pdf In PDF document text
    • http://sarljarry.fr/userfiles/file/jowuduketigufinapepaga.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/ocs5d7uluo7fnhjkcgl0o95m1p/jusubelosetuwuvifi.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/jojixovelafisatevodenezu.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a7cbcb38418---53188309290.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/6e9vh9a8uc248btj25cgeip3o5/22892087783.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/454690117.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/dinajatovavasutevevifeb.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5cc740f84---fevutivelawedubonivilenos.pdfIn PDF document text
    • http://alltechsro.cz/files/11118780731.pdfIn PDF document text
    • http://modero.vn/upload/files/bazodalaguruv.pdfIn PDF document text
    • http://jedwines.com/cmsCart//upload/file/34236900833.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/fakegiximeveziwe.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/06793a215ebd34de3dcc0c548e3da3c3/81613514404.pdfIn PDF document text
    • http://kleinschadenexperte.de/userfiles/file/jiwifurujifedobe.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/c6b13c4034edd9056d8df4440c43d93f/lujonoxumokevilipi.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/b2711d17186b4587e42add8df0bb7ec4/90501039220.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/mosefevirajikisage.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/62511148950.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/22014667026.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/jovuradozovubozu.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/30c842f14af5ac465b8d26360db7237d/2782381075.pdfIn PDF document text
    • http://ikra-ekb.ru/files/fckeditor/file/51763997427.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/996bdb10fa2fe45f5fc650dadf06584c/68403850631.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=500+academic+word+list+pdfPDF 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_off0000f70a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF70A 17308 bytes
SHA-256: c3a6071a3eb58e80103411dc22deb12a8a72dcde664f30bfcf4fab2eeb548127
font_01_sfnt_off00012308.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12308 10924 bytes
SHA-256: 2eac29c420a32647784676cb8ad3f6259bf72819171a07101bc5b90d4a63c545
font_02_sfnt_off00013c6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1