Malicious PDF — malware analysis report

Static analysis result for SHA-256 91eddc2bdcb91d0d…

MALICIOUS

PDF

79.6 KB Created: 2021-09-19 01:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 61bdda64ce2ba8d80bb53bb0bbca454f SHA-1: 6c1e7410afa6573c1759b8723395302ad9434fe8 SHA-256: 91eddc2bdcb91d0de0f4a401b11907faec7321ce1842f2b20f651d6d247172ef
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://allytemp.ru/uplcv?utm_term=para+que+sirve+el+modo+seguro+en+android PDF link annotation
    • https://cet.sk/res/file/52400017106.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202109091818494942.pdfIn PDF document text
    • https://vietnam-pump.com/userfiles/file/tutagubidalopeg.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1613335a6d2750---37521435800.pdfIn PDF document text
    • https://iqrainternationalschool.org/_assets/files/logonifokuxuzotepojolo.pdfIn PDF document text
    • http://jca-t.com/fck_image/file/riwiteridobokepolorujexav.pdfIn PDF document text
    • http://thumpamonpally.com/userfiles/file/kutozitelotokuxinaki.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/2jb33amogtrpo0sgsofbl9pvms/90296047247.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/daxawivogifaxunarubodebus.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/89024800713.pdfIn PDF document text
    • http://boilerservis.ru/uploads/files/2150637677.pdfIn PDF document text
    • https://mimpishiosatu.com/contents/files/vufaxebewunofizini.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/dumilumilibajole.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161344d8f97e15---waduzatajor.pdfIn PDF document text
    • https://interconformity.ro/images/file/tasowovovegujazimeti.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/gizidesi.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/47070523430.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/navudunefe.pdfIn PDF document text
    • https://digireg.se/upload/49797951689.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/vikeberiv.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/boserefepaxibewiki.pdfIn PDF document text
    • https://tierrettung-in-katalonien.org/ckfinder/userfiles/files/60242284065.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/67134061583.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/33212345224.pdfIn PDF document text
    • http://cluster006.ovh.net/~greeters/be/ckfinder/userfiles/files/83668518227.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_off0000cfb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB9 19176 bytes
SHA-256: 01a4c86383fbf7b70e1c32454bea6174256bdf2f0d63d4cc3cedc57da3b2c92a
font_01_sfnt_off0001002e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1002E 10804 bytes
SHA-256: a06a9ca2120b4132df775b6c3e8c292332ba025a5a226fcec21f5e2a2682e41f
font_02_sfnt_off0001188d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1188D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1