Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb86ddddbacfa203…

MALICIOUS

PDF

76.8 KB Created: 2021-07-01 13:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d50108c43730f581c1e7c464999d2a16 SHA-1: d5b63d53771cd13cfc09e26f6eca61d6cc9cf747 SHA-256: cb86ddddbacfa203e194a1d57831de45e4a582290ea1d45311ff0747ee294f7f
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload directories and other disposable hosting sites. These links likely lead to phishing pages or further malware downloads, consistent with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://catamma.ru/uplcv?utm_term=bma+talent+and+olympiad+class+4+pdf
    • https://soudurelausiere.ca/upload/editor/file/fusizipimegupidil.pdf
    • http://greece-ex.com/42921409918.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/sbcjoadjultrp7aerq27j8lvp8/lowove.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079bb0bbe9cd---nusuretoselijogaf.pdf
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/39491bb0f13faa0673fec1f83a9f5211/40047403266.pdf
    • https://aimara-bg.com/userfiles/file/xuwuwesomopozikofaviwij.pdf
    • http://ufnk.fr/app/webroot/files/file/bebewamexaj.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd489236fa2---bawexovager.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be666b037ee---64440931916.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160890cc80189c---pifegerewi.pdf
    • http://foto-video.ch/userfiles/files/majonufogunepavak.pdf
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/53234609ea9293bdb3d6533375e74ec3/xajotosulemuguwixen.pdf
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/ce35da78dceaa85ce17a0f7ae6093360/sojovuwukurax.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/bgg65elg2od7vnglafll6cvkm2/jinupo.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16090085e6bf17---dotelobowobidozepolu.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16077da80944b1---11853788710.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b63676bb5---17953312891.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/em5b9d23djdo32tvb9jfs93qd5/kidugiwajonuwavarabagus.pdf
    • https://cuacuonbentre.com/upload/files/mopusuwilaxelomitemesugiw.pdf
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/oso21cpa21flbpsdcr7mvhkni7/finavejanaragujidu.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/i7ijm604p1gbj4d134mkem1qp5/jowepadonokodatemebonakif.pdf
    • https://nikosdimos.gr/userfiles/file/kagonupafexobejubewilu.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_off0000c6c8.bin
9421b1d5a324802960957e23d41426d30b5513a5e899eef26766c65d25faf337
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C8 16904 bytes
font_01_sfnt_off0000f2e1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E1 16792 bytes
font_02_sfnt_off00010af8.bin
34d9c7ec3040f39b6a2a2c94e34e6bf3f44c04b8fc8144c191d4a544d51a7cb0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF8 10928 bytes