Malicious PDF — malware analysis report

Static analysis result for SHA-256 21cbb28b8ab6ce95…

MALICIOUS

PDF

96.0 KB Created: 2021-07-21 01:57:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: aafc8aa6f84ae20b890f6ff205476373 SHA-1: 6e3c84794a00401f0026758785de02c3c928c49c SHA-256: 21cbb28b8ab6ce957d346451f301175c3bacb29e8dfe4fc489c46964067b7eda
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of link farms on potentially untrustworthy hosting suggests an attempt to obscure the true destination or host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0093f38269---bumozonun.pdf In PDF document text
    • http://bezagsecurity.cz/userfiles/rogozo.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/faguzumemarire.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/bizoja.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/1lpefi5ppnviisd7n5tnk48nf6/6282008290.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160744608aff85---kibubofowow.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/5238d1bc7af7eb218d51c2351d462293/lajegar.pdfIn PDF document text
    • https://songhong.info/userfiles/file/konoginovi.pdfIn PDF document text
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/buzefagomedixetavij.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210713042313.pdfIn PDF document text
    • http://usmleworkout.com/files/file/tupiwelijinus.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcf900a1d5---65641855456.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/jodibafino.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/96422509554.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/tne95sr2qgr70mj3kfiersvqq6/8953788638.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096da7d244bf---dolaw.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/rtgs7lprnt6v5rftfrc7plisq3/1918679177.pdfIn PDF document text
    • http://zonwering-belgie.com/ckfinder/userfiles/files/30859504291.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080539966a3a---64596681329.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160cad75cdb7a2---rejivagizizititazizi.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/4khgb0lrktos6oj0qdcavv04fr/kojevujoxumebugezo.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/78342290304.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160c1477b19102---4777970232.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160800c0073f10---guzul.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/86952644726.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=expect+resistance+a+field+manualPDF 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_off0001104b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1104B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12862 10848 bytes
SHA-256: cc13dd6820b920c3b10e844cdb55091ecf9638e03365477459635ce4207b8a2e
font_02_sfnt_off0001416a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1416A 19672 bytes
SHA-256: 320195bc0d57c266fad866787b0634c67a949e3aca9fdb303c575ad5e92ca502