Malicious PDF — malware analysis report

Static analysis result for SHA-256 57a4dd973ca05fbb…

MALICIOUS

PDF

75.8 KB Created: 2021-10-02 15:06:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2a4b9a55e4f7bb7bb33e7fa8a6c01b0b SHA-1: d4cd70017062792db3c8eedc3341fa3a31125961 SHA-256: 57a4dd973ca05fbba29cf0b876e8c26f87e9cdd4ac52761e339d5990eb35b19b
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links to various domains, many of which host other PDFs, suggesting a link farm designed to obscure the malicious intent. The presence of a direct IP address link and a high ML classifier score further indicate malicious activity. The ClamAV detection as 'Pdf.Phishing.Trojan' strongly supports a phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://rcvizovice.cz/ckfinder/userfiles/files/davubogutemaripepalip.pdf In PDF document text
    • https://a-guskov.ru/uploads/files/19062697264.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/1614820fa0f546---64240771326.pdfPDF link annotation
    • http://tataservice.it/userfiles/file/13277368410.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/97466458666.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/sogom.pdfIn PDF document text
    • http://rtm-plus.com/ckfinder/userfiles/files/28240391198.pdfIn PDF document text
    • http://sitoad.com/bbqjoekey/files/202109131951082163.pdfIn PDF document text
    • https://oazapiekna.com/zdjecia/fck/file/kamepisuvipusezabubore.pdfIn PDF document text
    • https://larioenergy.net/uploads/file/xuretipuwaril.pdfIn PDF document text
    • http://asacnfservices.com/ckfinder/userfiles/files/53926690881.pdfIn PDF document text
    • http://bubb.cn/up_file/file/naxukaworebapuderogidotos.pdfIn PDF document text
    • http://dytac.hk/userfiles/88370209026.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161497f53e00bc---39328274772.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/839d4a822bca25c5228ecd7bd8669ee0/magubuxonapo.pdfIn PDF document text
    • http://sieuthimaynhapkhau.com/upload/files/73626199307.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/falesalanivexizaxiku.pdfIn PDF document text
    • http://mydreamtuscanwedding.com/editor_up/69451838409.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/80018451738.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/93419051119.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/53462090940.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/dimitekibonepiri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=lewis+structure+for+sulphate+ionPDF 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_off0000bf02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF02 19128 bytes
SHA-256: 6e41d7195971c2e8c11066a9d2bbe4fb21a000e7331a77bc7f29906b9a599bae
font_01_sfnt_off0000f09c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B3 10720 bytes
SHA-256: 67bd7c943de054de30adcd2c0d90c29db25d597f2e090584de5bc04a35b9541a