Malicious PDF — malware analysis report

Static analysis result for SHA-256 a98123b15d46a4d3…

MALICIOUS

PDF

70.7 KB Created: 2021-09-24 17:36:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 034cad0ac678a7f4bee75749054a990d SHA-1: b5e4093c2fb2454f2070a236a8513044c806d402 SHA-256: a98123b15d46a4d311705a864586ea6869c5ac8ff99d68c498e340539af604c5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm strategy. The presence of these links suggests an attempt to lure users to malicious sites, consistent with phishing or malware delivery. No scripts were extracted, but the overall structure and URL patterns strongly indicate a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://oniceh.ru/uplcv?utm_term=types+of+wild+pigs PDF link annotation
    • https://pensionradvanice.cz/res/file/7002234134.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/161486ab01346b---nasedikofogejurofigamuji.pdfIn PDF document text
    • http://xn-----6kcftbqgtghjv5bf5gydg7b.xn--p1ai/files/files/58802180898.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/zinitijaxixawolube.pdfIn PDF document text
    • http://nature-revive.org/files/file/4615650129.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210920/2158044710.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/f89d790b9626eb46a996c797e6635bef/vusawututusunefamajel.pdfIn PDF document text
    • http://aroma-es.site/yamituki-n/uploads/files/52376763163.pdfIn PDF document text
    • https://thomsonindia.com/userfiles/files/tasorirojelinenivedugiki.pdfIn PDF document text
    • https://delphin-restaurant.com/ckfinder/upload/files/37265493691.pdfIn PDF document text
    • http://0851gay.org/userfiles/202109file/2021092322565670554.pdfIn PDF document text
    • http://potya.com/64531831017.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144e38413920---retobabapitaxopujijuga.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/jspj4afr3gb049jtses0804j10/gomeseviwug.pdfIn PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/sezusixenabigurupe.pdfIn PDF document text
    • http://www.koeru.eu/failid/file/terorajud.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/14094086901.pdfIn PDF document text
    • http://fourfoods.com/images/files/danumavukuvolenupevogo.pdfIn PDF document text
    • https://slezanie.eu/userfiles/file/faviro.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/91611002314.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/920445654.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/85025423796.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/202192124956936.pdfIn PDF document text
    • http://liderzy.natura2000.pl/imgturysta/files/luxoregosejamukokekupen.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/tk78lbll01fgl30fbpoo81c8u3/rogegozibaziparajixup.pdfIn PDF document text
    • https://sterlingsez.com/ckfinder/userfiles/files/gijevedujomisewum.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b33e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB33E 10372 bytes
SHA-256: 4355c371e8205ec8b439afe66bb2ea4e17e71fafd3147ba2f840d2284cae4577
font_01_sfnt_off0000ca9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA9C 16652 bytes
SHA-256: ebeba2c90279a10887b0d1ac76caf4b5d8de81e5f7dcac96386e6a9b0a6b3a71
font_02_sfnt_off0000f598.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF598 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1