Malicious PDF — malware analysis report

Static analysis result for SHA-256 556564dd93a88a20…

MALICIOUS

PDF

74.4 KB Created: 2021-09-08 18:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 92cc58a58d3af4a36c9869930a32e039 SHA-1: 9cc3ef3e92381693652e72cee13a4511809d8af0 SHA-256: 556564dd93a88a20892976258db728517a5ad3908b78a873d7eaa5f3c58fc416
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm, including links to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://daiichitravel.com/uploads/news_file/65043078140.pdf In PDF document text
    • https://luathoanghuy.com/uploads/files/bobam.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133deb059986---baganufajor.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/38732664590.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/wezubodoroxokakemibil.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/tobujuno.pdfIn PDF document text
    • http://l-max.ru/userfiles/file/pejevefakikuzusetijiwi.pdfIn PDF document text
    • https://kapefashion.com/files/files/vogilokidupoposetedin.pdfIn PDF document text
    • http://fsnmmaterials.com/UPFILE/userfiles/files/42608168550.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ebcc86ad0---kufedaxovut.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/romuzibajopiresiragi.pdfIn PDF document text
    • https://wojczak.pl/userfiles/file/bugazo.pdfIn PDF document text
    • http://logicamail.it/draft/media/44032119440.pdfIn PDF document text
    • https://cakenflowersonline.com/userfiles/file/79386252367.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/wumoluwavu.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/92714681691.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/saduz.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f15325c152---41256082152.pdfIn PDF document text
    • http://tecresconsolidamentorestauro.it/fck_data/file/33365918750.pdfIn PDF document text
    • http://kaies.cn/upfiles/210905225549782741pykxnt.pdfIn PDF document text
    • https://quangtriasianwindow.com/uploads/image/files/75643009246.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=balancing+redox+equations+worksheetPDF 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_off0000bc8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC8F 17508 bytes
SHA-256: 90cac58014c0581a56dddcf2f8cf222ce49f8774a87af75d4390f5f1b09c897e
font_01_sfnt_off0000ea88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA88 11228 bytes
SHA-256: 2d461448ca6e8c56d2b0ec8b0444240f24595ba8376b5b37e8d80105640f1594
font_02_sfnt_off00010465.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10465 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1