Malicious PDF — malware analysis report

Static analysis result for SHA-256 c08cbd746a12bbb9…

MALICIOUS

PDF

74.2 KB Created: 2021-09-27 04:14:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d0f18b5bffe9d914daf7183f0fe5db24 SHA-1: 78500d6996e370c8bbcf7605f4084cd89d0f31e0 SHA-256: c08cbd746a12bbb9dd27389e7c44c2502d6d335fc1396748b93e204688ea41e0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to various PDF files hosted on different domains, suggesting a link farm or distribution network. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a potential SEO manipulation or content distribution scheme. While no scripts were extracted, the sheer volume of external links and the ML/AV detections point towards a malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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.
  • 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://servicepapik.ro/files/59813099374.pdf In PDF document text
    • http://jawarakreasi.com/file/javot.pdfIn PDF document text
    • https://terrebleue.org/userfiles/file/708257072.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/fibadikimozarewifur.pdfIn PDF document text
    • https://ulsantour.com/FileData/ckfinder/files/20210927_FEF28B951335B744.pdfIn PDF document text
    • https://micsys.in/userfiles/file/zigusadudumidifojunisosar.pdfIn PDF document text
    • http://ekorepetycje.eu/Upload/file/58786293181.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614bc21568222---71651780095.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/pafijilolelinela.pdfIn PDF document text
    • http://hk-keber.de/images/file/fumalekeb.pdfIn PDF document text
    • http://tumwebthailand.com/ckfinder/userfiles/files/23145436540.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/19132496547.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161462896b8c33---34330838162.pdfIn PDF document text
    • https://aep-tc.com/cache/fck_files/file/netufepodijexabibizoju.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/76346750260.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/96102649795.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/jujudunegafuzexamefowo.pdfIn PDF document text
    • https://stpatswatertown.org/ckfinder/userfiles/files/varumubuvobopexovibobema.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/7858006708.pdfIn PDF document text
    • https://totounited.com/contents/files/buzugujifiliruramijemite.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/gugosuduj.pdfIn PDF document text
    • http://www.moyekolodin.com/files/69004463106.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/20617742286.pdfIn PDF document text
    • http://chip-chup.hu/upload/file/zopuzulekenoruzozazosepot.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=t+shirt+design+yayprint+apkPDF 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
stream_002_off0000b623.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xB623 10676 bytes
SHA-256: 421721b6024b9a09be395effd5f46eafd1314e64aef01b4743851c25f66d388e
font_01_sfnt_off0000ce5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE5B 20256 bytes
SHA-256: c9b65a4b5bd3da9d3d70d3c6bead04df345cfaf811e46835e5c79db84ef9a4b1
font_02_sfnt_off00010335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10335 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1