Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f6b31c55a166f9…

MALICIOUS

PDF

72.9 KB Created: 2021-09-03 13:46:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 53d570b938ad0768c7c5b92679a20a2f SHA-1: 1ea04858b29a54f62865e53ca18b50dcce318b54 SHA-256: c9f6b31c55a166f98907b5afac979ec42f74318ccacb3753027cabc11bded4b6
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://0975811252cool.linker.tw/files/62939843330.pdf In PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab00a44572---60091526477.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4c33b0c3e6---badezimilodisom.pdfIn PDF document text
    • https://qkon.ca/images/file/gomomowuwe.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6f31c9f53---12988501980.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/ioo8mbusg0okgejott7fhfqn3e/3188506975.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/63711845006.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/bd7c9be670c45b89e4ab8edea5e62f17/24708102427.pdfIn PDF document text
    • http://yingtailong.com/upload/file/210825092838434942zh5hugugbldd.pdfIn PDF document text
    • http://poiskvod.ru/images/file/duzexeromikuta.pdfIn PDF document text
    • https://ymy-tea.tw/upload/files/furot.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/2021828_171833_161.pdfIn PDF document text
    • https://carparts-fixture.com/file/file/83435357501.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/kemogumurogobaloxuf.pdfIn PDF document text
    • https://widepolymers.com/userfiles/file/xikoloxuzesamerazono.pdfIn PDF document text
    • https://clickbox.ro/images/file/4652256108.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/jotilewofupegog.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4148921ab---pitifo.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/7196713016.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/3562218485.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/8ab23b69fddafabe623513db9b2b0a7b/31371032640.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/24e7f509de8201cb073ad07256cdf624/86877971631.pdfIn PDF document text
    • http://dentish.ru/ckfinder/userfiles/files/mumupujesafazodazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=york+aircon+operating+manualPDF 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_off0000b9ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9CE 16836 bytes
SHA-256: 1a0fc28a300447405d10bab6539e2504a279153ffa7518a9a0452473ddb78864
font_01_sfnt_off0000e5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F7 10724 bytes
SHA-256: 28295d5a631991452a55320981d2d57738f4aad0a576862c8bc2b80b38a71f69
font_02_sfnt_off0000fe95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1