Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4dc12b6c0819d6b…

MALICIOUS

PDF

77.5 KB Created: 2021-09-17 23:52:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0b64376535b455bc28d8dfbc8321bc58 SHA-1: 132da4a4b645e564f9313b48ba94950883baf0fe SHA-256: a4dc12b6c0819d6bc967fcd443216aadf9b0f3bc24641b5b9369e409a1bff804
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are hosted on disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://gsxr.hu/userfiles/file/xedezabezitalabiv.pdf In PDF document text
    • https://0955205219.jwa.tw/userfiles/files/foboxonegar.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/pepimibimagane.pdfIn PDF document text
    • https://goez1.com/10005001208290177/ckfinder/userfiles/files/tasir.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/notawikufebamenidat.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/68196220359.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/75279517560.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/090722289375.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/25503617098.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133426c45291---63951774816.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/keloverawe.pdfIn PDF document text
    • http://tjtvina.com/Upload/files/semorumejamada.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee01f45016---nirupiwepupevojofagaki.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/lojamaxeko.pdfIn PDF document text
    • https://www.hkfew.org.hk/ckfinder/userfiles/files/43215547263.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/lapaxiwagigaweranu.pdfIn PDF document text
    • http://studioingegneramato.com/userfiles/files/rotimelovu.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/luxemunatogakojowoduno.pdfIn PDF document text
    • http://zhxndl.com/uploadfiles/files/lekenapududuwika.pdfIn PDF document text
    • http://noclegsosnowiec.pl/eurostyl/photos/file/zolir.pdfIn PDF document text
    • http://wellgroup.cz/UserFiles/File/37198649772.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/49040509732.pdfIn PDF document text
    • http://gaishachuukobuhin.com/js/upload/files/dirisatasonazozuvuwiduvew.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/74661801711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=games+for+android+4.2PDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c8e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E6 10676 bytes
SHA-256: 2279ed695ae0189ac72bab304bc88866a8c342eea86e614f0f72d2afe4e54ff8
font_01_sfnt_off0000e167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE167 18244 bytes
SHA-256: 12e971fdfbab13c9220d44c687c7ede089478a4772b3e3d8808c11a6db6ce223
font_02_sfnt_off0001108c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1