Malicious PDF — malware analysis report

Static analysis result for SHA-256 f721c23c4328ad4c…

MALICIOUS

PDF

79.6 KB Created: 2021-09-12 07:17:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 26b832b36393c57734c3f41fb02f1492 SHA-1: cab9d2e80a6502657ed6f200f62761c3db3a3c31 SHA-256: f721c23c4328ad4ce61ffbb23af4d90648146e4acf659c41cc2e064b2a1a432b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristic firings indicating it is a link farm designed to redirect users to other malicious PDFs, with a high-confidence ML detection and ClamAV signature match. The presence of embedded URLs and the PDF structure suggest an attempt to host and distribute further malicious content, likely for phishing or malware delivery. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://ifaistos.reality.gr/~triantaf/images/file/29228545109.pdf In PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efb75232a5---71161095349.pdfIn PDF document text
    • http://jmvlpslimited.com/ci/userfiles/files/37004074203.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99482101900.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/vamuba.pdfIn PDF document text
    • http://nationalherbo.com/userfiles/file/60536283618.pdfIn PDF document text
    • http://steakpluspizza.us/userfiles/file/8739274834.pdfIn PDF document text
    • https://stthomasorthodoxchurchsouthpampady.com/userfiles/file/66611445069.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/xawepivujani.pdfIn PDF document text
    • http://nincity.de/inline/file/73514204199.pdfIn PDF document text
    • https://e-casainteligenta.ro/userfiles/file/zoxagibazovakujikukosego.pdfIn PDF document text
    • http://suachuaspa.com/upload/images-content/files/19232700637.pdfIn PDF document text
    • http://namlinhchisapa.com/userfiles/image/file/kojarojozu.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/86254872631.pdfIn PDF document text
    • https://olivierdaulte.com/ckfinder/userfiles/files/lawikeratijo.pdfIn PDF document text
    • https://srinivasagroup.com/ci/userfiles/files/64542695474.pdfIn PDF document text
    • https://pvesc.vn/uploaded/file/fawovovowenokavexadawe.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/nuwifemokebimesere.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/dd50f66dacddbf49ad8cbb59618e8ea5/50818028420.pdfIn PDF document text
    • http://stonebreaker.at/60092187521.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/rilikikole.pdfIn PDF document text
    • https://istanajpdua.com/contents/files/ludironivulepapigejilupo.pdfIn PDF document text
    • http://studiopol.it/userfiles/files/10286074784.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=zenonia+2+apkPDF 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_off0000d224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD224 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA36 18688 bytes
SHA-256: 3a1f3d523871f607b566180dbaa2e57fc9d6d1ec9dd9d5a8aec485107377dde8
font_02_sfnt_off00011b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B32 10008 bytes
SHA-256: 7c9f5e306e364c9382be773306e87b10101199471b10f568228c3256e7a507d0