Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cb8840ca9eb23d3…

MALICIOUS

PDF

85.7 KB Created: 2021-07-14 02:45:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ace60e905281652a4ad6d5e7e3677c94 SHA-1: 9bf1e7041bcaf4134e4ab92d0a99df2159abb955 SHA-256: 1cb8840ca9eb23d3651fcd907851eada5d7a689d186d00e00143d6b92ff47898
196 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a remote-support tool lure. The document's structure suggests it is a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, likely to host or redirect to malicious payloads. No scripts were extracted, but the overall pattern indicates an attempt to trick the user into downloading and executing a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://sxcec.org/userfiles/file/52967761804.pdf In PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/09d093778e346e828c25249eb60c50b2/lokuzamavivafunapikeba.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0be8c1fb2---84228809712.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be81d4c62a6---wojejinelikidi.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/38401681839.pdfIn PDF document text
    • https://laser123.com/geektic/files/76289861579.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/kkm1diqvpf8fhqa7mk2q08v234/69617550781.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607272034af33---18360515767.pdfIn PDF document text
    • http://tfforming.ru/d/files/64756656970.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608755857f07b---topejanatawe.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/93683243881.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/8kmd8hg3kev37fjm8k9t4mv95v/suvelolugex.pdfIn PDF document text
    • https://bevelec.com/bevelec/dossierMois/file/godosoberepuvuwi.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16075617cdad02---97892291680.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/58sk83u6nv9gjrot4g6bdbsu0e/pibugarasanutowakolumi.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/gexija.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609193ec896f2---gidunaxazediwukotimuwiri.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b115d4481ac---14093144094.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/a64a7b3abb9dbfc77ea66c1b0986b0ba/luvuvonutuxirepig.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4b0ef3cf1a---94720877982.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160817d7d84861---ladivuvusexa.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16074462cde3be---dududagiganininaxobebajo.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/20804570718.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=relation+between+frequency+and+velocityPDF 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_off0000e597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE597 11000 bytes
SHA-256: 1b7b110aae57dbb78252fa20069afba00f9c9ac899e527e12248bb6c2de4bd93
font_01_sfnt_off0000ff1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1A 18760 bytes
SHA-256: 1ec9d7b62f55ab6b7606331d7f2d80a1c7277506fb98b75edb005f7037d7b363
font_02_sfnt_off00013167.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13167 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1