Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac759ff8904df38f…

MALICIOUS

PDF

74.5 KB Created: 2021-09-28 15:43:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8906f79c3700216d03b85c6d6af6c2ba SHA-1: 2d0101730b3709ecf48ea065cac380a82be5fe1b SHA-256: ac759ff8904df38f031df9a55ff610d944d7ce1ffb9beab07d271491933485d2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple unknown URLs and a compromised upload link farm are the primary indicators of this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://clingac.com/d/files/togulifelu.pdf In PDF document text
    • http://balcimimarlik.com/resimler/files/62952946614.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/58821999119.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/suvetesapamubofulubosej.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/c0b56997d0e10d177e5be33576ac882f/fumifixelifunelodiwi.pdfIn PDF document text
    • http://agrion.org/upload/fichier/nuvusijusetebexosene.pdfIn PDF document text
    • http://ssaisarang.com/ckfinder/userfiles/files/munekorunekize.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/65761710763.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/92987766649.pdfIn PDF document text
    • http://ventss.ru/userfiles/files/37212317587.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a80162f09---goweda.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/kaxifufebebamowagofodozu.pdfIn PDF document text
    • http://futboltotal.net/images/files/vepunubuzujixosimi.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/pawijuna.pdfIn PDF document text
    • https://horkolas-gatlas.hu/ufiles/file/73738270048.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/d395c5d98246d9bb5691d62bb94e2c85/81702730424.pdfIn PDF document text
    • http://www.moyekolodin.com/files/29544723915.pdfIn PDF document text
    • https://v-rshine.com/upload/images/files/45601430259.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/tedugukatel.pdfIn PDF document text
    • http://nonstopsushi.com/uploads/files/79845380987.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/budujupadovuzidonagifale.pdfIn PDF document text
    • http://wawa757.com/uploads/files/nimosik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=android+system+webview+updatePDF 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_off0000b90e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB90E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d120.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD120 19524 bytes
SHA-256: afb0b493e186409b15ab11dbfe8f9beb13fa85a55dbc43ffd9583ea1c0466978
font_02_sfnt_off000102f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102F1 10992 bytes
SHA-256: 0577d82542d21bcfb932c61b89812d8bcd3086069b2c11e6c55711de9f5d6ceb