Malicious PDF — malware analysis report

Static analysis result for SHA-256 57a453af72bd3993…

MALICIOUS

PDF

79.0 KB Created: 2021-09-02 20:45:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7f4b80a73a2f0d82ede5fc389b57c69e SHA-1: 071d26d189b59c4c039f05eac33ac62355fb434f SHA-256: 57a453af72bd3993d6fa93625abc3d688665e6fd476d3f932aa4298db7f6d6b6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as a phishing trojan and the ML classifier indicated a high probability of maliciousness. Multiple heuristics identified the document as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting. The presence of embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ylphs.com/ckfinder/userfiles/files/11844378808.pdf In PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160861c9fa6393---guxaxosuverelenan.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/66860177192.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/sirugomidewanoseda.pdfIn PDF document text
    • http://giacongcomposite.com/upload/ck/files/68798506017.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/76206773475.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608575127e3a9---kijozarapibevufi.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/9974890544.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe63ccdf31---giriwajezimapem.pdfIn PDF document text
    • https://asi-filter.pl/files/file/67968942.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160afb033479da---1523770499.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070252d85cf6---nepabitijukewegum.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160876d6fd35fa---1101222084.pdfIn PDF document text
    • http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/10074466675.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082de79b21b5---xakomofawu.pdfIn PDF document text
    • http://hmed.vn/upload/files/dojasiwe.pdfIn PDF document text
    • http://dothi.info/images/files/pegupawemakel.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bobunasinetam.pdfIn PDF document text
    • http://clinical-pain.com/pds/userfiles/files/povotomawirepulog.pdfIn PDF document text
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/94390851341.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/juxuzepojopaguv.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a07bbc22e89---18739180830.pdfIn PDF document text
    • http://canxetaianhduc.com/images/file/dajojijabuf.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/55896550178.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=programma+per+scansione+in+pdfPDF 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_off0000d04f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD04F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE861 17640 bytes
SHA-256: e01307cfa4f07e5cd8aaeb1fdf161a29133bf130a235a5e0d3b5e51c3192fc01
font_02_sfnt_off000115e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E4 10820 bytes
SHA-256: c56b4a291727e69c95ec942888b063a0fe891b4fb5fd7fa9725a00479efd5611