Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c8987c742885d70…

MALICIOUS

PDF

206.8 KB Created: 2021-08-01 00:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 03a6494174eb4e7b18f56b4677ae86bd SHA-1: d0528cf718630cd7dc96f596a91ec2f5de5d632b SHA-256: 3c8987c742885d7024632faf2e286533d9086bd423ddd230b0adbca7437fa629
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and multiple external links, including one pointing to a compromised WordPress upload directory, suggests the document is designed to either phish for information or download a secondary malicious payload. The use of external links and embedded scripts aligns with common techniques for distributing malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=respuestas+del+libro+achievers+b1+workbook PDF link annotation
    • https://lordoptika.hu/files/files/borovoxosidigukudizaro.pdfIn PDF document text
    • https://circolodelpistone.ch/userfiles/file/zibofulesujed.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-7-14/20210714012101640452.pdfIn PDF document text
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/xusavusopixokalixixiludo.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c342377b092---kazaferaguvibopoj.pdfIn PDF document text
    • https://scriptdd.com/_file/file/78656560206.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/48966401459.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e51d05f409---pobixivesaguledulobeted.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/87039606500.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/qb7h8mt9trr2gjifm9at729uvi/3647457401.pdfIn PDF document text
    • http://szguilong.com/userfiles/files/wirudu.pdfIn PDF document text
    • http://jeansresource.com/js/ckfinder/userfiles/files/kumodaxujerate.pdfIn PDF document text
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160b1116514ab8---81500328413.pdfIn PDF document text
    • http://csc021.com/userfiles/file/20210623092006_soxrwm.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/60817504987.pdfIn PDF document text
    • http://uleshuzatshop.hu/files/file/38595560775.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff010340c1b---deguvobugerajiguzulapimu.pdfIn PDF document text
    • http://ya-ke.cn/admin/upload/849679582.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/57924264883.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/le8mdh3ph6461nq4vm41f9hkm1/wewusotutotokagikerapejus.pdfIn PDF document text
    • http://regalmotors-jp.com/js/upload/files/ranenezavefa.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_off0002c5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2C5C6 20084 bytes
SHA-256: d3f2bb58462aed1a973644dcb2e812104c80ee6b4916581237d892969a7d0c80
font_01_sfnt_off0002f99c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2F99C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000311b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x311B3 11088 bytes
SHA-256: 6c0aded821b86d4067610bd7fcd62baaf0e003d07a9323b2e6ab26def20d03ac