Malicious PDF — malware analysis report

Static analysis result for SHA-256 423cd08bea41b23b…

MALICIOUS

PDF

97.8 KB Created: 2021-06-27 04:05:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 10715893c04cc962fc6dbebd000c975f SHA-1: 333cde25d4be5fbba3e2a36491f232a50d08cd5a SHA-256: 423cd08bea41b23b060b86122f435e72ea004c94f24b5bcce7a3d53b86d32c56
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of external URIs and link farms suggests an attempt to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c164498fd7---xegag.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/3441a37763f93da35d817afdf35fd84b/59951334667.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/d2a71fd4c9ad80944437cdc109f6acee/15809394043.pdf
    • http://pvhs1967.com/clients/a/aa/aa78cb05297cd93d8a9ab6bd1eb8a3c4/File/42208203442.pdf
    • http://re-view.online/fckFiles/file/lowofo.pdf
    • http://naturabliskociebie.pl/userfiles/file/tepux.pdf
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b2bbfa50f8d---24554357337.pdf
    • https://fallsplat.se/file/wifaw.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/5637a6d1be688ccfbe4f81d5093bf131/ropudiwosegegiwojuv.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608f091b99eaa---45976287926.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16098748b198c9---73377814056.pdf
    • http://10glazsikeyrosa.ru/file/beminevajasa.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/shvokck1qb48a0p8774ua2veg0/raruziwiwuv.pdf
    • http://nacyc.jp/Upload/file/xakej.pdf
    • http://sarljarry.fr/userfiles/file/fesutukexalipo.pdf
    • http://bumsnab.ru/uploads/files/toselorirarur.pdf
    • https://angel-juicer.com/FileData/ckfinder/files/20210613_087F687817148185.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082fadcbad56---wabutijisirurigojik.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607077ccb3c8e---sizis.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a602dc4f199---ditufafeluzilosumifuwis.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9c72632cb---59704214308.pdf
    • http://zabradli-znerezu.cz/userfiles/file/25138340338.pdf
    • http://doubletroubels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f94fb07bf---degozetunusuz.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/9ba3bbf8b7fad8ef09c27bf41788ca12/4876456139.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=middle+class+monthly+income
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/27438d39a0b997b8e7c8716edfe1c5a6/jivuvumarojopetel.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_off00011c61.bin
e0a9be32f0b8962138c7ffedd68218607e0ebce2e5f7383d0dfcb058ec409d5d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C61 10644 bytes
font_01_sfnt_off00013485.bin
4c17a3c1f140cbf26a6869287f8629d5a1a7e17102a42d6381ce3d73b111c595
pdf-font-stream PDF embedded font (sfnt) at offset 0x13485 17348 bytes
font_02_sfnt_off0001622c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1622C 16792 bytes