Malicious PDF — malware analysis report

Static analysis result for SHA-256 18931b0d426b7c31…

MALICIOUS

PDF

74.8 KB Created: 2021-07-02 04:54:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: ca9c85a64449c8bd12a15e387cd8739d SHA-1: 8b907307dff6c1ee54a76910c1afc9749a636852 SHA-256: 18931b0d426b7c310f5bb34bd942c18f33f0381f322a19eb11381b52c8ab4c96
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS uploads and disposable domains, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to distribute further malware or engage in phishing. No scripts were extracted, but the PDF structure itself is used to facilitate potentially harmful redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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://webinaris.net/ckfinder/userfiles/publics/files/xinesotuzulamovegemitap.pdf In PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608c16290af64---9254001813.pdfIn PDF document text
    • http://twxcd.com/img-aim/files/9339417075.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/06463e03620e6b77c66df19ccd984870/bonejijigoliz.pdfIn PDF document text
    • http://nena-artspace.com/ckfinder/userfiles/files/tafibad.pdfIn PDF document text
    • https://m-isc.com/userfiles/file/21568308611.pdfIn PDF document text
    • https://12shio2.com/contents//files/tupufaxowogaguzusorux.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/st8coirhtj0fbe0a0m8ogpsq3p/42552288352.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/829bc2e96692b35537b10f9d8375fb2e/22553921759.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/mamolovu.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/95122749477.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8f41495af---16403431818.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/265716533f92778243b47c05a316cb2a/zivejowovinawimiramaroje.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/dubekivijapov.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/55b42c03f288bcf847ecd5e7d598ebdc/30568726496.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/93836139571.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e43950cd9---29168370261.pdfIn PDF document text
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/0e5490c16f6545cdcecb7c25c6f8c48f/81928182153.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/2ec718298efb188b7aa66129f37a225c/tixatiniwezebakevopire.pdfIn PDF document text
    • http://short-story.ru/upload/file/nonebereba.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072233e2e5df---mesapaliganidiwo.pdfIn PDF document text
    • https://toskov-yordanov.com/userfiles/file/gibibisexasawoxamo.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/48703030986.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/kuzaz.pdfIn PDF document text
    • http://thedreams.cz/files/ratakutegesiwifemomiwapan.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/pixegogoposanipelujeg.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16084994e1d739---75997591792.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=writing+algebraic+expressions+worksheet+pdf+with+answersPDF 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_off0000c20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC20E 11312 bytes
SHA-256: d68a14611e2a76e0a97d0f9f89f8ef5341bc9378c5ce9a77627a113ac360b38e
font_01_sfnt_off0000dc32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC32 15888 bytes
SHA-256: 576ba98b7a0d04f763307062fbd98f67a2487cd1fca53a244e2d6390960747b8
font_02_sfnt_off00010535.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10535 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1