Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9849386eb0debed…

MALICIOUS

PDF

74.1 KB Created: 2021-06-30 19:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b7b48d711b8a036e59c75c7457d416ff SHA-1: 22d813ded0db8deab52612909258f060ff79ca72 SHA-256: a9849386eb0debed895cf8b8cf15797614d9983ef171c93498afd8f0bbaa9ad9
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to numerous compromised WordPress sites and disposable hosting, likely to distribute further malware or phishing content. The presence of many external URIs and the 'link farm' heuristic strongly suggest this PDF is designed to redirect users to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/bq30m10s2jhhv6tt61mkl6pqgm/75209434694.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e899bc7e4---wuzegu.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608134a393ba3---potunusofef.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85036374f2---56132892592.pdf
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/wewopiderurufesotibeloxo.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/fcbb14c0863b016360aa7877cd4d24e4/85521560934.pdf
    • http://voszveszprem.hu/_user/file/kefirow.pdf
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/3f3c3ac8d9601e6f0be7e42273a70a3a/83294673540.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/f0fc5b8b98edfa04646d16acdd342872/47834454361.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/tmp/91967145538.pdf
    • https://soudurelauziere.com/upload/editor/file/fofiwupojebemazazizuzos.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/q9ljqeialec7lpgsarrv8aao34/dasopuxidipulego.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a32d17208e---83205143020.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c525fd8ef73---68718654615.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/bic5u59ike7ub0m4212kv7kajk/7699508650.pdf
    • http://panda-es.tokyo/yamituki-n/uploads/files/xavefomosomijasitukin.pdf
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/dc619f7c8559c1565690d2ecf6b62258/74757089221.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e338d4cc2d---67736541740.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078acc9ec2ce---sonomereka.pdf
    • https://ludifrance.fr/userfiles/file/51128407070.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/31204e87fd72396fb8e1e6aa38058956/44431270463.pdf
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16079f1ef2a8f1---rakew.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/52fad90fbddbf96dae8f97af237eb7bc/68767468246.pdf
    • http://rolmech-strzelno.pl/Upload/file/48987492338.pdf
    • https://artasedanasingaraja.com/uploadfck/file/34523472807.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=transient+ischemic+attack+in+chinese
    • 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_off0000c362.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC362 16792 bytes
font_01_sfnt_off0000db79.bin
15ca6f14815bb2381b4d97166e656e1548701b7197cf88c452007c2535a89ecf
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB79 10384 bytes
font_02_sfnt_off0000f2c2.bin
ae84353773433547f7000c540a36532c53b5cab38472551a3627aa82750b25c7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C2 15644 bytes