Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c4b2d23cec8329e…

MALICIOUS

PDF

76.0 KB Created: 2021-09-20 17:11:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 01b915ec0768a5df35bd0ee78819cb07 SHA-1: ef056eb9f942551f7ec9a681d70b5ca549e8fa7c SHA-256: 4c4b2d23cec8329e439dd6c8d492df33b93caba33d33e63a98d2c5a8e8a0c146
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating it is designed to redirect users to potentially malicious websites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://irlanc.ru/uplcv?utm_term=gangstar+vegas+highly+compressed+100mb PDF link annotation
    • https://ferest.ro/imagini_ws/zakekakewi.pdfIn PDF document text
    • http://marchmontnews.com/imgs/file/88701456969.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140201ca8ecc---gemura.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/fuzizoginifojujamiloz.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/tebajupefuzutesonomam.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/bosobarebowadupesakipibu.pdfIn PDF document text
    • https://fitness-sport.it/userfiles/file/70202451056.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/zosemu.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161425fe8d3679---38460154911.pdfIn PDF document text
    • http://salt17.com/userfiles/files/xupelowegopevarisefenuwen.pdfIn PDF document text
    • http://www.satunatc.ac.th/ckfinder/userfiles/files/52853857119.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/85456013254.pdfIn PDF document text
    • http://studiotecnicofrisoli.com/userfiles/files/sasaja.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/boximivipomemivazum.pdfIn PDF document text
    • http://www.extramas.com/userfiles/files/faximupitemoxegunik.pdfIn PDF document text
    • https://ikitellirezistans.com/upload/files/jirimafanodufi.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/jisafibupenolanimiruvate.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbe5253600---varabunoxokad.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/90193099878.pdfIn PDF document text
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/72442761248.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/kutigufudi.pdfIn PDF document text
    • https://biholka.cz/uploades/userfiles/file/85475562569.pdfIn PDF document text
    • http://familie-schiecke.de/images/file/jasowakowokeliwunuwipimi.pdfIn PDF document text
    • https://medtek.vn/storage/file/20004608588.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147cf8f4d6bf---rifaboro.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/samazonafuj.pdfIn PDF document text
    • 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_off0000c410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC410 11492 bytes
SHA-256: 5dfb97a5281a63f24b4f3eebba29ae803a419495eb39e131f19a8ffbf05a4149
font_01_sfnt_off0000deb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C9 16776 bytes
SHA-256: c77bfc98eef5e4b2fc057ebe4b5a058efefcf9ab2d3fe077bebee343795a924b