Malicious PDF — malware analysis report

Static analysis result for SHA-256 598e31ab8afb9e29…

MALICIOUS

PDF

89.8 KB Created: 2021-07-31 03:57:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7d90b61a8cf871bc7461534e8c3ef80 SHA-1: b52c412544a0d95a0c5859ccc6db5bd59a21e86b SHA-256: 598e31ab8afb9e29efcc62d6256dcaee0af25ce7d95fb565d4fcda8ed880bd5f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF was flagged by multiple heuristics as containing a link farm pointing to compromised WordPress sites. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The embedded URLs suggest a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160705a7c8b430---vomaxuniniwapir.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f87411938---relimujorumupukasa.pdf
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160815b48640ce---logedeximirepamonikowawi.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/a12f139407a2ebbd0facc1131d6f8742/16973289246.pdf
    • https://vandolderskb.com/images/usr/73258974555.pdf
    • https://karinbentum.nl/uploads/file/4969869734.pdf
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/df179ffb130d7e9a9fbad7efccea7ba1/voromawavadozisebeve.pdf
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084aae8e6cf9---vojiwel.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/cefdc0a1602604fc1d6fc5856c44d056/zunudotupalezadide.pdf
    • https://tangente-mag.com/img/file/1930550754.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae4b30869d---xozukeg.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c63a197f2b7---salep.pdf
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/840a718f844d3cd5b044444f393ba50c/84800779351.pdf
    • http://kotolantopeni.cz/file/vezinanapowejagom.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bda54f7fde4---delositotapojepunug.pdf
    • http://mestav.sk/uploaded_images/file/8549646423.pdf
    • http://ohappy.org/userData/board/file/99694881753.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160885a05cbb05---42794986814.pdf
    • http://gdbchurch.com/clients/43262/File/32682455713.pdf
    • http://gilendor.cz/userfiles/file/kipusajuzapelitikuv.pdf
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/16c016ec9fa8f7466c2cabbb68c35f73/tipunusir.pdf
    • https://bwawarszawa.pl/upload/file/dawisodilapuxisutiweno.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=alien+shooter+2+mod+apk+android+1
    • 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_off0000f377.bin
7d5371b23c7190cea0724d688671d32f38b9d9580eb25ebfe1b32a009e0d3087
pdf-font-stream PDF embedded font (sfnt) at offset 0xF377 10900 bytes
font_01_sfnt_off00010c9f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C9F 16792 bytes
font_02_sfnt_off000124b1.bin
95886e2f224141a8651142e614063df023a4c875cc0fc83024cd7fa08ec41876
pdf-font-stream PDF embedded font (sfnt) at offset 0x124B1 16952 bytes
font_03_sfnt_off000150e0.bin
3f1748778f03e7b7e2d3a6c88ca15ef060a02f224cd71155e662fde9dd4c56c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x150E0 1672 bytes