Malicious PDF — malware analysis report

Static analysis result for SHA-256 6623965845cb5943…

MALICIOUS

PDF

82.8 KB Created: 2021-06-28 13:46:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c1ca9db19396b1274fd78faa3de3f0f0 SHA-1: ef2be8b201b1ca1e2ba1e2e32f5bbf35468eeb72 SHA-256: 6623965845cb5943c612145f76fa2366ab6932f1e8496ffffbac9dbf84bf117b
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://heyumpnd.com/userfiles/file///48461497518.pdf
    • http://zwickerfoto.hu/_user/file/zumabofelogupesojuw.pdf
    • http://zoltysnieg.pl/pliki_wyswig/files/bipumomuzak.pdf
    • https://autosaloncenter.com/uploads/file/pelufebaxaz.pdf
    • http://noxsun.com/jingkelun/userfiles/files/20210617131708.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d89c1f9a9---gilofemijuxida.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073a0f0e2c56---sekufopubilufepenupisef.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc3d1027ac---tiwafovegapotobob.pdf
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/adc746ac07856a4552a4fdccbe4cf701/46806562308.pdf
    • https://detectiveoffice.net/userfiles/file/39622946001.pdf
    • http://duonglaohanoi.com/userfiles/file/zatilewuzotopefurate.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a6212eedef1---9564673064.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f1763e3f81---88776133148.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c417522d1e6---27669824711.pdf
    • https://baptistfriends.org/media/nabububarojuwosixazubepup.pdf
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094d5fd678d5---vudotokozigememubawezized.pdf
    • https://vasantviharproperties.com/userfiles/file/62412150169.pdf
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/motagofuwajikika.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bab451ac8f6---bazigoxukib.pdf
    • https://bursac.net/userfiles/file/13036274499.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/8be2c3b0371f039c890497cb972fce67/50813216157.pdf
    • http://pincailight.com/zk/UploadFile/file/2021062700300273499.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a74e6d2c02f---murufe.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e90e218480---busipidijagovo.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d89cd632a5---56732983346.pdf
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/63179973676.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=medical+surgical+nursing+bsc+2nd+year
    • 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_off0000e062.bin
a2cc4e74aae5da65e3396c60efa7b225f9af2eb2bbd53d21e8fbf72def70fa05
pdf-font-stream PDF embedded font (sfnt) at offset 0xE062 17140 bytes
font_01_sfnt_off00010cfb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CFB 16792 bytes
font_02_sfnt_off00012512.bin
0746ae0a4e68d2e7ea9d72d06c8a47fff330eab7446198dea433c23780671717
pdf-font-stream PDF embedded font (sfnt) at offset 0x12512 10792 bytes