Malicious PDF — malware analysis report

Static analysis result for SHA-256 88833b7e6628fdff…

MALICIOUS

PDF

82.5 KB Created: 2021-09-23 03:34:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ee1dc0fefe0b0545554923188a820c9 SHA-1: 68d27348c7ffd5cb5223adcaaac35451777ac05e SHA-256: 88833b7e6628fdffb054370bd12ece5881e92ac6931868d0380445351f345af2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, forming a link farm. The presence of these links suggests an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/kezurexozalomikasuvorav.pdf
    • http://congtyvima.com/images/Download/35631973248.pdf
    • http://trunghungplastic.com/luutru/files/linifipokuku.pdf
    • https://stockbauer.hu/uploads/file/tusabitu.pdf
    • http://seksdagen.nl/userfiles/file/bimol.pdf
    • http://feynburg-uhren.de/uploads/zezisuba.pdf
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161446db73a773---ziwetaje.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/18f66abdc8bf000f8a177497673ab5aa/luvowedebezopuzu.pdf
    • http://support-cmu.com/filedata/file/fenorejizewogoxiluj.pdf
    • https://makanbanyak.net/contents/files/14588605765.pdf
    • http://bestpokeya.com/uploads/files/11896297733.pdf
    • https://pasarantogel.com/contents/files/rukoruxuluxarajir.pdf
    • https://ayurmitra.com/files/file/biwavekif.pdf
    • http://tecnoservizi.com/userfiles/files/xafejidapagitoli.pdf
    • https://masukpt2.com/contents/files/17587968797.pdf
    • http://facilitymanagementassociates.com/survey/userfiles/files/35936892641.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614425d99a959---jebodopiwunobewu.pdf
    • http://abnig.friendship-match.com/upload/files/moxorezaxaparoworafilije.pdf
    • http://omni-links-europe.com/images/blog/file/89145770877.pdf
    • http://xiangzhuan.tw/upload/files/gasag.pdf
    • http://yoshitomo-kokubunji.com/jcfiles/file/zizubowosajafapa.pdf
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/16145ba13559f2---sisuwipetuwisinologij.pdf
    • http://sumosushingrill.com/uploads/files/jelogeteridiworevifiw.pdf
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/5c51fd180194d8eb921b4f49be6ab927/votewamejepuveramulobip.pdf
    • http://gangwonbnb.com/FileData/ckfinder/files/20210901_63183E3DF0E56B41.pdf
    • http://biurod9.pl/public/userfiles/file/94543830845.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=friday+the+13th+the+game+mobile+apk
    • 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_off0000dc22.bin
a724e1934b1889dcd4686296d8d38e7a251c82c8dcb1503af18759450a93eb13
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC22 18152 bytes
font_01_sfnt_off00010b35.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B35 16792 bytes
font_02_sfnt_off0001234c.bin
4c157b3936d9bbf16e9f70de32410253d3baf54ec56d1639b4ca7d765acef95d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1234C 11116 bytes