Malicious PDF — malware analysis report

Static analysis result for SHA-256 88d669bc5b1546ca…

MALICIOUS

PDF

75.9 KB Created: 2021-09-04 02:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b1a64a9ffb7c0e4285ab6cd5c430da8a SHA-1: 2da62ff0d40c3ef36f024a9bffbd4102eda5f12b SHA-256: 88d669bc5b1546ca25a3df03bd5aded4f0b8f8572aa9d3664115d22900d8daa8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by multiple heuristics and a machine learning classifier. It contains numerous embedded URLs pointing to external sites, many of which are hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The presence of 'utm_term' parameters in some URLs indicates tracking, common in phishing campaigns. ClamAV also detected it as 'Pdf.Phishing.Trojan'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://garglob.ru/uplcv?utm_term=origami+steps+pdf PDF link annotation
    • http://akcjonariusz.com/UserFiles/file/50440302034.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/ledewufona.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/37875971344.pdfIn PDF document text
    • http://xn--80aafbjcazdrhzgiddbbcsg4l.xn--p1ai/pict/file/9250674289.pdfIn PDF document text
    • http://elsekmont.eu/userfiles/file/7148894958.pdfIn PDF document text
    • http://teleinwestor.com/userfiles/file/solidemujarotasoromob.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/85670072924.pdfIn PDF document text
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/58733452690.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/naginejopusodedagajad.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/40428564326.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/35510147689.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/bababo.pdfIn PDF document text
    • http://nenkin-t.com/upload_img/ck/files/70034525258.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8dff64d4f---tasurisilotubagigoluxa.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/67540754667.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a32acbe31---82100009858.pdfIn PDF document text
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/bojovekiwokeli.pdfIn PDF document text
    • http://relatives-united.com/clients/75139/File/xamururuvulunumalifato.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c28a6b918d0---fiximoga.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/6d55f0d73098d6e945a4702e18659872/zofigidinamutoxenimapom.pdfIn PDF document text
    • http://antonellascarpittadesigner.it/userfiles/files/34681022329.pdfIn PDF document text
    • 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_off0000c304.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC304 18108 bytes
SHA-256: ca2928083078c60dd8c2d4d510e603d98a0de00d289a465a8dab74c67af061b2
font_01_sfnt_off0000f243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF243 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5A 10596 bytes
SHA-256: 84e31d13b2c93cada58ecc7d76d67eb5e093fb4902ad5d45a031c5db2c0f7d0e