Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a0cd8b74cb78091…

MALICIOUS

PDF

94.3 KB Created: 2021-08-06 07:17:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c53846759114af31f315da12c49e41a SHA-1: dca1781de46e2c45d79f6dd156ec6a0ff4026cd7 SHA-256: 4a0cd8b74cb7809150974b3c040403c4dd822a64d4d45a5e764efbfeb5d688b9
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the PDF structure itself is used to host and redirect to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://smidgel.ru/uplcv?utm_term=home+depot+garden+center+jobs+near+me
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4030bb923---pebumagekapoputikaj.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e0d3737381---bimawobadasikowotojimur.pdf
    • https://valenciamaids.com/userfiles/files/ninasewesurixolaji.pdf
    • http://weymouthhighschoolclassof62.com/clients/5/50/50fe23896e84432c97ff20d680692bb9/File/16257904148.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e001a6037c1---77149233253.pdf
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/85168298319.pdf
    • https://seeandhearbetter.ie/img/shop//contents/xozotimowotavekula.pdf
    • http://pogservice.ru/userfiles/file/34569786019.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5cf9702b8---jajedojesolo.pdf
    • http://qlinairnv.be/userfiles/file/26800881546.pdf
    • http://buydecor.ru/uploads/files/pipiviwagofopo.pdf
    • http://alphabodysupplements.com/newerac2c/userfiles/file/gumubugusigelag.pdf
    • http://yejida.com/userfiles/file/limitemuti.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1b663e2ca---75067164247.pdf
    • http://artside.org/data/temp/file/63093441451.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae721754fc2---nunumujulesibozipegixiloz.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16100a887b61cb---favedewukukukiv.pdf
    • http://a9188.com/upload_files/art_files/files/20210619_172118.pdf
    • http://gerd-pollak.de/userfiles/file/78739960254.pdf
    • http://toyotarent.tw/FileData/ckfinder/files/20210726_EFCB7676608F6A9F.pdf
    • https://alihuata.com/userfiles/file/56397433295.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/gdhkejf6ae5iplert0ok5jl5a0/gidoloxiropemeboz.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f76cea0e7c458a6668c2fbd56e809bba/welexagipulilopowu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010d81.bin
3b428eeab0878588f69039533117c648833e268dd5e1fb0fec923b86faa46a45
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D81 16996 bytes
font_01_sfnt_off000139bf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x139BF 16792 bytes
font_02_sfnt_off000151d6.bin
16915aedf7c0ef1c724af8b40b461289e27adeca611534b31576842d8d1ab0b9
pdf-font-stream PDF embedded font (sfnt) at offset 0x151D6 10980 bytes