Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f9377d680c55f1…

MALICIOUS

PDF

83.6 KB Created: 2021-06-29 21:46:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a5a1b7b09271ca036c815a5b86e144f0 SHA-1: 15f1565a810d1fd3effe0e0bcdadfbc75fa168f7 SHA-256: 51f9377d680c55f1498426b621cb83684dc544733803e114b5119bb7016a2d25
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. The document body is unreadable binary data, suggesting it's not intended for direct user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/d20kq3a16pn2e9ct5dioll2f42/xonidori.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160986ae09fc9a---28249663759.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16096f0d04dbd9---82794231638.pdf
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/151bcf98123857f13e19f294c9167852/2729977973.pdf
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/1620e83e3529627fc1327e2b6eed88d4/napitim.pdf
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d79bf43b66f---51193065655.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082fa7219346---bumuradigovi.pdf
    • https://fl-forever.com/upfiles/editor/files/kubesozojujunezeduzij.pdf
    • http://pension-erlkoenig.de/img/editor/file/59251424666.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160809ca9a19ed---95090605654.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0987a6311a---28629770593.pdf
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/78256745572.pdf
    • http://inlovehuahin.com/file_media/file_image/file/wajozil.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/0125942d07d6f375e0fb3359a788de73/96737789750.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607614a8339ab---35342370919.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/ab86a54bb039725bf4a8f20a33403c87/zedev.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e7136de05---doxakad.pdf
    • https://vishalahospitality.com/ckfinder/userfiles/files/paretorinalatil.pdf
    • http://capmar.eu/userfiles/file/20017010444.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac113ac5a7b---56883077621.pdf
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/34583561363.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16097942491d9c---92988658814.pdf
    • http://cbestdesign.com/ckfinder/images_store/files/joxovigorusowozukelunejuj.pdf
    • https://mingyi-lock.com/data/file/userfiles/files/legesim.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=partial+fraction+rules
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e352.bin
50bdfd066266a6f34a6ec32b207610e6c22f998636235f86b897dcf19bc6b871
pdf-font-stream PDF embedded font (sfnt) at offset 0xE352 10428 bytes
font_01_sfnt_off0000fb16.bin
ba8c7189688bf2be85e697f017b69884cd8d73e313e5a7ed1f7648f269b58063
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB16 17380 bytes
font_02_sfnt_off0001290c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1290C 16792 bytes