Malicious PDF — malware analysis report

Static analysis result for SHA-256 d28f95a96ec8242a…

MALICIOUS

PDF

69.7 KB Created: 2021-09-14 08:48:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cd007603e0ada6394dda6a1ae4807caa SHA-1: 30c5414353a8775d958db46d7c3a0b9790f9d6ef SHA-256: d28f95a96ec8242a3e6d2261447c91efab5ae63111d228ca789edcf882ccafc6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which are hosted on disposable or compromised hosting. The 'utm_term' parameter in one of the URLs suggests a lure to download a calculus textbook solutions manual, which is a common social engineering tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://pickup-ws.com/userfiles/files/wazinawiw.pdf In PDF document text
    • http://dexgerm.com/data/file/userfiles/files/xivediniviniwos.pdfIn PDF document text
    • http://pokebarslo.com/uploads/files/pilegamegokaxixojarofavu.pdfIn PDF document text
    • https://mimpishio1bet.net/contents/files/55709402445.pdfIn PDF document text
    • http://na3.it/misc/file/tazedizofitotam.pdfIn PDF document text
    • https://kakakmanis.com/contents/files/76199589815.pdfIn PDF document text
    • http://27derajat.com/assets/ckfinder/core/connector/php/uploads/files/vajogexonekomopodexoma.pdfIn PDF document text
    • http://eqletstalk.com/uploads/files/202109021022338780.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210910_0D355B92284A6529.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/vavagosiroxebenujixogez.pdfIn PDF document text
    • http://evolutionchonburi.com/userfiles/files/befixinalolejafep.pdfIn PDF document text
    • http://kleinschadenexpert.de/userfiles/file/79037690044.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/kegixalupimidavuz.pdfIn PDF document text
    • https://lacaune.hu/userfiles/file/52740603538.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/kefonimuferekusujotufodi.pdfIn PDF document text
    • http://rancholasmonturaspremios.com/campannas/file/votefazafa.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032ac02b0c---zokutelodejuxovopiwo.pdfIn PDF document text
    • http://colegiosantarosa.com/uploads/imagem/file/74288309901.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c80e505201---88375953044.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/161356e746a395---20326882641.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/31152020000.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/64412104293.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=stewart+calculus+7th+edition+solutions+manual+pdf+free+downloadPDF 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_off0000afab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7C2 11196 bytes
SHA-256: 08ecdbaacb24df994cc9b49504eca1728528a1e0ca78ad175c6fa9fe106379ab
font_02_sfnt_off0000e1d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D7 15436 bytes
SHA-256: f9a476de6a5ccedc36bdcb8c8f2fa3a2988ad2c3210c74e05dbf91bdd8294a82