Malicious PDF — malware analysis report

Static analysis result for SHA-256 f91f8a311d736a5e…

MALICIOUS

PDF

94.7 KB Created: 2021-09-23 05:02:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 49113f3f5eb4e33040ebb3ff9ca7d873 SHA-1: 153ee49c632dce3f274fdf28bfd34786e72a84e8 SHA-256: f91f8a311d736a5e8bed08ba35ec38f9414a320b92f1c054b59a9610b80da645
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan payload. It contains numerous links, many pointing to compromised CMS upload directories, suggesting a tactic to host malicious content on seemingly legitimate but compromised websites. The presence of a link farm on disposable hosting further supports a malicious intent to distribute harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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
  • 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://yjsyrj.com/userfiles/file/64173568740.pdf In PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f437c25f98---84055613055.pdfIn PDF document text
    • https://angkoronetour.com/userfiles/file/88436879481.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/1111a07faaf6f3f8148582e80f723f33/10373150516.pdfIn PDF document text
    • http://qataminational.com/uploaded_files/userfiles/files/30040904447.pdfIn PDF document text
    • http://boatmonies.com/uploads/files/rakigenukibabopapemuvapu.pdfIn PDF document text
    • http://nenorm.com/files/files/xutadiruwati.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/6952840416.pdfIn PDF document text
    • http://skoleniridicubrno.cz/ckfinder/userfiles/files/7165231390.pdfIn PDF document text
    • http://motopujcovnateplice.cz/userfiles/file/48031189620.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/sevelogobosavevejuzozit.pdfIn PDF document text
    • https://www.mtiwelding.co.uk/admin/ckfinder/userfiles/files/bewufemadobuwoxuxolun.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/duxusi.pdfIn PDF document text
    • http://xn--b1agpbmdtf.xn--p1ai/upload/file/gaweteralufobidasugexer.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/lekeleve.pdfIn PDF document text
    • http://amandamaitland.com/images/file/fotobixanugip.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161471e6a8065f---95472121966.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/30013270dad90e489bed3ca52d9d0892/pininizisudom.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/velimoserobazeroga.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/9a672343f19c5382498bb320aeac84fb/dopinogogasekukuposupemon.pdfIn PDF document text
    • https://dogathermalhotel.com/resimler/files/wunesowibafesepamov.pdfIn PDF document text
    • http://dogalakustik.com/depo/sayfaresim/file/7609619133.pdfIn PDF document text
    • http://sccsfz.org/upload/2021-09/fexedogofewi.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf154d5b1d---79454554167.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/rixipejow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=www+smart+cricket+live+tvPDF 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_off00010f08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F08 10404 bytes
SHA-256: f4be8a6ed268a2db3b40c4d20c4fdd9b464bb407745e9c9a4281fa2463b9b8f8
font_01_sfnt_off000126a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126A2 17960 bytes
SHA-256: 7a78f12384aa63c8c9d1d5af775a5143e780a4e94646925d7b41921d206d8d85
font_02_sfnt_off0001556e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1556E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1