Malicious PDF — malware analysis report

Static analysis result for SHA-256 645dec43176f4716…

MALICIOUS

PDF

82.1 KB Created: 2021-09-07 09:02:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ab158c052c8f7131cc4a2f6d19dfd0eb SHA-1: 50d9c7d4dd86cc6cbc17a416554b592ceb8d4eb4 SHA-256: 645dec43176f4716e71be582afc215b85156d7e43cc80cde181d7f16302e3511
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites, some hosted on disposable domains. The presence of external URIs and compromised CMS upload links suggests a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://wastran.ru/uplcv?utm_term=book+thief+pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611766ee22e0d---risabafagavurezav.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/105a4f55e761dd5e76b227b66569485b/bimisiranapufaterosamupa.pdf
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/427d84cb7a7b97ed240ce0b04b2109fe/kebagufokaxixuvixeninumu.pdf
    • https://vate-tire.ru/wp-content/plugins/super-forms/uploads/php/files/4140786da2d3b88939e4fe540c086663/gafiwepefevozapovix.pdf
    • http://youzedu.com/ckimages/files/20210818162731769177.pdf
    • https://www.chablis-gautherin.com/ckfinder/userfiles/files/8218648296.pdf
    • http://hobbstownis100.com/clients/6/66/66141d04a4341350d76ae3a38785cb5a/File/93572045737.pdf
    • http://cedarvalekansas.com/clients/875954/File/vazetive.pdf
    • http://osc-pribor.ru/products_pictures/file/70822601009.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16089bd8bbc87b---23791763540.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610a12edbac29---56338954962.pdf
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1182646a4---tobog.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/91743412947.pdf
    • http://lube-stc.com/ckfinder/userfiles/files/26692775251.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160762f632eae9---zegipotikiledef.pdf
    • https://jodhpurtravels.com/nbloom/fckuploads/file/22928234589.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a06f8631fc---munuzepep.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/e0ec151e7c2bab776b0f70902284b233/39135785128.pdf
    • http://jingyilin.org/uploads/file/35424608509.pdf
    • https://kingdomofgodmn.org/userfiles/files/80388986984.pdf
    • https://autoteam.in/ckfinder/userfiles/files/likugagofab.pdf
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/7pilr8rhj4f6ncivar1jbjdfok/topaxemoju.pdf
    • https://samirkumarpaul.com/ckfinder/userfiles/files/zamogatenenubarawumet.pdf
    • 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_off0000dd72.bin
79a6a7421c68e82c9986eb0651df18bf65290417f10834379d1ee93f9677da2e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD72 10160 bytes
font_01_sfnt_off0000f455.bin
58da1a702fea1d43d28f46728b75d1d2a1bb42a9cb948a9ad0e8f968f5f997b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF455 18032 bytes
font_02_sfnt_off000122db.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122DB 16792 bytes