Malicious PDF — malware analysis report

Static analysis result for SHA-256 1573904631e99116…

MALICIOUS

PDF

84.2 KB Created: 2021-08-31 21:12:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6358f8fccc2859bd1d7f4ff61c8436f7 SHA-1: f0ad22b8ec3038f3877acfd44b5fe074359f505c SHA-256: 1573904631e99116a34ec4130af89bd2d2d000f94dcfee3a3f16154cdca7c27f
156 Risk Score

Malware Insights

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

The PDF file contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The numerous distinct hosts and the use of UTM parameters in some URLs point towards a coordinated effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://nomylo.ru/uplcv?utm_term=slow+cooker+pork+and+butternut+squash+stew
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160894abea005a---87625518262.pdf
    • https://weddingitaly.jp/images/file/rexetuxovorofekaxitoroka.pdf
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16092ce9c7e410---mufagukavafonu.pdf
    • http://geometramaurotozzi.it/userfiles/files/tejukelibabebadofulu.pdf
    • http://mientrungland.net/uploads/image/files/tewar.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608f08edefab8---kikinorogur.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/0923441f4f642bba67f2308812bf1155/velexonuxabozamigenot.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606d370e2c13b---6293618290.pdf
    • http://profil-metall.de/content/uploads/file/fimiwa.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/7d4320470dae2deb778002254bc2cd54/divan.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/d23c63a530c78f3f30780ddf7234c3f5/mumiruz.pdf
    • http://iproperty.ae/userfiles/file/67905820714.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaa7170fab6---11821112424.pdf
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/2jqoohd2m4ja9mcqp7d0n9k3r7/guperafuvegerubize.pdf
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/do3n3le5kcsndu9bk0daglimr8/70767987097.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/jlo84q4e46akvkg0nk5feo95n1/digelagupipe.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/kc5pefeqm0vs292869qurohcd7/tulax.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8e4fc0a46---94395502662.pdf
    • http://kashima.cc/userfiles/file/18967688439.pdf
    • http://ros.by/ckfinder/userfiles/files/28305080460.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/8a294a322a6d8c2ddbf810fd48e0e9dc/xudubugit.pdf
    • http://fullcolorspandoeken.nl/userfiles/file/78937606849.pdf
    • http://xn--d1achljw0b.xn--p1ai/content/upload/62319509589.pdf
    • http://architettoseneca.com/userfiles/files/81705322143.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/02c6c60ab3cd7e6d10fd88b64bccb2af/68248249552.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_off0000e246.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE246 16792 bytes
font_01_sfnt_off0000fa58.bin
4238fcc957a7669db220ec3cf54f9ee7425463a5d5aa053e9c0e6228f1f5ec06
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA58 17804 bytes
font_02_sfnt_off00012864.bin
18c4f68380b5ab3f9e9ccb7e3be6517e2c876b62b66fcf8f00ec6e7e9534548b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12864 11160 bytes