Malicious PDF — malware analysis report

Static analysis result for SHA-256 88278dac3b6693dd…

MALICIOUS

PDF

89.1 KB Created: 2021-09-03 01:32:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 76699ef3420beb0c65110b68bfd5c150 SHA-1: a8308b6c37a6df70e199f5d9c643a2acc46ce5d0 SHA-256: 88278dac3b6693dd9d215221057775438c65696a5ca8bd60661ede935019c2b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics indicate the PDF acts as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

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 http://rapabzenec.cz/obrazky/files/xudukepetokugolamige.pdf In PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f317d05b0---92067130641.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ba96d9005---diguwenope.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/08b10a2a645f42dc6465c2337602f9cd/10688679546.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/wugedojejokezelojuw.pdfIn PDF document text
    • https://www.acetechnology.co.in/wp-content/plugins/super-forms/uploads/php/files/hthtcpr91q5jfiqjvo60d2oi1e/kipusuxupajena.pdfIn PDF document text
    • http://magooferta.pl/uploads/fck/file/tegoxopiwerugugukavose.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611f4748441c0---kuvowanopezaderili.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/bezetubabijunajepowupat.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/porumusejojite.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b58be6a805b---89397538956.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f6357d719c8---fivajokawegebutuxetido.pdfIn PDF document text
    • https://girl0229960192.com/upload/users/files/29925195279.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/fivuramojukutasonafewit.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/lejewew.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/bumositoguwi.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/jjbflf5ghtc5b58jb7hn73bui5/wemedinurikosur.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/533d8c932a80aba24ea5a8cbe6ff3404/gusenuvemunisolelesip.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b63a12b261c---pazaju.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/1hs8k5oov9bd6sdu0dt46mrqj0/60554407398.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/juo8rfrpk2t9l6q67r101a5aek/71779832075.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/ggelan495bbuaas6hoopr39ob1/lowowomovasusolerekafa.pdfIn PDF document text
    • http://kusadasidentalclinic.com/img/userfiles/files/83220205592.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=%D8%AF%D8%A7%D9%86%D9%84%D9%88%D8%AF+pdf+%DA%A9%D8%AA%D8%A7%D8%A8+top+notch+2PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c90d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC90D 17708 bytes
SHA-256: 10e8bd1e26c12db8933b9ad512b8ceb5080fe0f15de84e3cf18a077102ae9355
font_01_sfnt_off0000e44a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44A 25540 bytes
SHA-256: af1aaa55d7a5cef75999ccdabd5db8b538ce90d32a351f045d010a507ce40f93
font_02_sfnt_off000122f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122F7 10040 bytes
SHA-256: 99849ea1ea39881583f020a2c0c8f40359534e501c897f2ef9113a4c701fcc60
font_03_sfnt_off0001392d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1392D 17600 bytes
SHA-256: e23622d476f8e369da2ac55b07bafedc64dee9fb18750cb6a1d968b25e037e30