Malicious PDF — malware analysis report

Static analysis result for SHA-256 d320858e2c3405a2…

MALICIOUS

PDF

83.1 KB Created: 2021-09-19 02:18:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c30908f143bcb19b7c0825540f66bd0b SHA-1: cc81da41c66043efb426bfbad3ae2f36b9add2f6 SHA-256: d320858e2c3405a2eec58ef1052eaf8932a498b7f3b6ba8be1633a2ba8d898ed
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL targets are indicative of a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a20af818ce---61177940883.pdf In PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/8b84b43f8950da8a575d95a055cd5daf/7806373287.pdfIn PDF document text
    • http://industra.sk/userfiles/file/nojojozederesu.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1613f230a76b4d---89307882286.pdfIn PDF document text
    • http://bndweb.nl/upload/files/10799769361.pdfIn PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/xivipetis.pdfIn PDF document text
    • http://winso.tw/userfiles/file/68738367470.pdfIn PDF document text
    • https://loonbedrijfschimmel.nl/userfiles/files/nuxufulu.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/16988172146.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef80034cb6---63249175964.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/9d20bd4ec6cdc01dfce0be72bcb8729b/fimilum.pdfIn PDF document text
    • http://china-baby-clothes.com/d/files/3496263043.pdfIn PDF document text
    • https://tsolisp.com/files/file/83045412161.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/17447640799.pdfIn PDF document text
    • https://dm288.com/slicice/file/16567058666.pdfIn PDF document text
    • http://magendans.com/imagefiles/file/limofelufapifuje.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140b9a6955e2---fesati.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/1601a9ff2d8660e117fea981d97c2e2c/jopizokaxofinisorewun.pdfIn PDF document text
    • http://effektfilm.de/files/file/36494173515.pdfIn PDF document text
    • http://sinners-party.de/media/file/zedebodaduripobisosul.pdfIn PDF document text
    • http://mlead.net/images/e/file/furaropuzodidotid.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/bawoparibanilaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=instagram+beta+apk+downloadPDF 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_off0000e2c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD4 16664 bytes
SHA-256: db8773dec2228d4093dc8cdd5ef718dd7a901e95a85a599ad5a58d5109218eac
font_02_sfnt_off000125bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125BB 10912 bytes
SHA-256: b33b646b896e347159181194a9d8d6f01eccc8b5b17e72aac0252b0b7af6bf22