Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1dabdce37dae1a0…

MALICIOUS

PDF

87.2 KB Created: 2021-09-20 21:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cd0b2208160fb4186abbce6cb45debbe SHA-1: 1d0acb965811a9806a2e3c7b767c002b314f996c SHA-256: a1dabdce37dae1a0c72512bee02e6ba90c2559e1de53bdad318f7eb2ce57e70b
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL heuristics and malware detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://bilafafafa.com/shopadmin/upload/files/lerefe.pdf In PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161451bc739598---nanofosisorupofu.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/xepolajalijegine.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130027b1a1f0---ziviludarexinubetapubip.pdfIn PDF document text
    • http://retrolondontees.com/userfiles/file/72701975395.pdfIn PDF document text
    • https://arendic.cl/files/41574777001.pdfIn PDF document text
    • https://cv-vezouze.fr/media/file/57106597728.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/d42a5a1ad51a60e5f6ddd8802d7f24d2/90254375756.pdfIn PDF document text
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/xeredujuwugaxufogovunabin.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/75874129686.pdfIn PDF document text
    • https://garnet-medical.com/userfiles/files/pozavugaje.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/79403447567.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ede056eb3---vekatifalenuvoxemakojav.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/purewimesijuxediper.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/93261870178.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/wejenazonemalaluzowota.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e1a1aa3180---tizukowibipaxegoxa.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/32007338350.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/fagopegetopozolan.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/masile.pdfIn PDF document text
    • http://queenart.kr/userData/board/file/tovorepofek.pdfIn PDF document text
    • https://cochleartudaskozpont.hu/files/bipekalarezefowiveki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+screen+share+chromecastPDF link annotation
    • 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_off0000ef82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF82 18764 bytes
SHA-256: d92e286229a3e0bbf010ea5049799880d34b422ad5e1e7b07282fac078c4a217
font_01_sfnt_off00011fc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FC4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000137db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137DB 10436 bytes
SHA-256: 9b99cf73f4e7534671f627a7be4c42f5453434d366e06eb5f470eec71ca50825