Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdf60a42685f73eb…

MALICIOUS

PDF

82.8 KB Created: 2021-09-12 16:09:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 39f89023d3996c3a14f204a1d510bce0 SHA-1: 4f6e46b34a163d0067852f3fc54b21b4d4f6aa55 SHA-256: cdf60a42685f73eb782c9a3deef2ac4dd24554bea3686bd97c34092f7768d462
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, suggesting it's designed to distribute further malware or lead users to phishing pages. The document body was unreadable, but the presence of numerous unknown URLs associated with compromised CMS uploads strongly indicates a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613409846d351---95529818644.pdf
    • http://vinmexindia.com/uploads/rifozewapemusunetizijod.pdf
    • https://hediyelikhanem.com/calisma2/files/uploads/jogutakesavesu.pdf
    • https://mamotato.ro/userfiles/file/73599156772.pdf
    • http://pate4me.com/userfiles/file/jepakuz.pdf
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/fidujemovaripobuximis.pdf
    • http://hophungvietnam.com/app/webroot/uploads/files/safes.pdf
    • http://stagegator.scorchmark.com/stagegator/ckfinder/userfiles/files/bofimivul.pdf
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/89988778629.pdf
    • http://hangquangauto.com/files/66936242807.pdf
    • http://primaneighbors.com/userimages/51551891803.pdf
    • http://red-persimmons.com/upfiles/editor/files/ludazisalakavonisijugu.pdf
    • http://cen7dias.es/userfiles/files/63728022515.pdf
    • http://take114.kr/FileData/ckfinder/files/20210912_37F8F82B1DE03436.pdf
    • https://ukmalayalamnews.com/userfiles/file/pagupu.pdf
    • http://dieta-plus.pl/userfiles/file/bufil.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c673362e3---31110621521.pdf
    • http://doo-san.com/userfiles/file/20210905184907.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134b044afe72---66073250488.pdf
    • http://petswithlove.com/cvsprojects/SSK/Source/2.0.0/images/files/58935942078.pdf
    • http://mibenjamin.com/userfiles/file/92707814556.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be4bda77cb---botesuze.pdf
    • https://serwisnawigacji.pl/userfiles/file/pibujasume.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/1au9nf6asrmlqcl3ig19ln362c/nolifosopev.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=alchemist+book+pdf+download+in+english
    • 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_off0000dc8d.bin
a8b3812b9468dd02860ca28453f4bc4d24052578161dfd8d9a78a9ad4446b9d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC8D 11264 bytes
font_01_sfnt_off0000f67e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF67E 16792 bytes
font_02_sfnt_off00010e90.bin
c9b09cadf051e421c9010706546c0e3f0a55cb818aa8dc22b066ce05291dafc0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E90 18168 bytes