Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac78335ec81d316e…

MALICIOUS

PDF

115.0 KB Created: 2021-06-25 19:48:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9f844b3cbc137303a980c9bd03e38bee SHA-1: d4d78e4660b84b354bff101c2ecd229112a717e2 SHA-256: ac78335ec81d316ee467497debd2b048e06f49c24d8e60743a978a552633cb1d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9871

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.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/52118813c556345386a3cc733ed7e35a/zalafewuwolo.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160bede861e553---zimibifumamunovulena.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/a8290ee812858a0165587a8d1ed2b635/63822008660.pdf
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/qtu2edg0j18k1jreevgg3pq8sc/81943742845.pdf
    • https://laatjehuisweerstralen.nl/upload/file/digavaj.pdf
    • http://sns.hu/_user/file/sileruwagul.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8fbf1853a---limirowidusafinorek.pdf
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/ecf244d658295d9f0b2553c778afca09/43196554255.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/3c7352533f6f1d6a40c18bafc52920ef/tutujonizadorelexa.pdf
    • http://fotofolliasanlazzaro.it/userfiles/files/14000997612.pdf
    • https://adikkedua.com/contents//files/60732009644.pdf
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/faeeb03f306445270deb68dfe03b6ccb/vubabat.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b0fe9039a---74571444818.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/2861c346a0c65e8846ee50a6bc9bb6f7/95346724589.pdf
    • http://vistobrasil.net/uploads/file/29796449098.pdf
    • https://petala.gr/userfiles/file/xavupasojegotosovukarapu.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/d4ee86467a2037b4898969961dc54493/zefivuxi.pdf
    • http://pumarecovery.com/userfiles/files/85322143927.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/c9c2c21f77f7181ae1848250b46b7e0c/lukozifalavenogid.pdf
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/96114287987.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160721f8d742e7---66496821920.pdf
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b12527d18f7---dajisutabenonurolu.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5ab125ecb4---35723763943.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6a8c5bc9a---guzudakagitafufepodili.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079899222ba7---49655612251.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=rocky+4+full+movie+with+english+subtitles
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014345.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14345 16792 bytes
font_01_sfnt_off00015b5c.bin
26dfd5f66f6d0c288f257fd7aa2b92f6bad31c370d02c96a0d577a916f4ed90b
pdf-font-stream PDF embedded font (sfnt) at offset 0x15B5C 11244 bytes
font_02_sfnt_off000175ac.bin
089cef905c1df7b66195924885aee5f9582c7e12cf5f2c0063baf71b47545504
pdf-font-stream PDF embedded font (sfnt) at offset 0x175AC 25496 bytes
font_03_sfnt_off0001b376.bin
682d445327b8b6ae025c5bc3742012d1738abac7c7359e35fde6a029226c42f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B376 2336 bytes