Malicious PDF — malware analysis report

Static analysis result for SHA-256 871931e357270373…

MALICIOUS

PDF

82.0 KB Created: 2021-09-05 12:57:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7528e9cf834667130acc80621f0c16f1 SHA-1: a1a2b1b4ecfa85851f71a0f60f195354ef7b9886 SHA-256: 871931e3572703739ae137148bc0e6578ba320c842cdeb831e8fe221d5e19942
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm. The embedded JavaScript (T1059.007) likely serves to redirect the user or execute further malicious actions. The numerous external URIs, many pointing to compromised WordPress upload directories or disposable hosting, suggest a phishing or credential harvesting attempt, aligning with a Spearphishing Attachment (T1566.001) vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wedding-photos.cz/userfiles/file/mexedewu.pdf
    • https://timjanen.se/anvandarbilder/53/files/najabudubodolevise.pdf
    • http://moscowfashion.net/content/xuploadimages/file/mirekuminemezugedegalari.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160833a688ed25---5319566965.pdf
    • http://studiolegalebisantis.it/userfiles/files/50658050923.pdf
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608c198bf102d---fexesudanegubuduzo.pdf
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/5b2d48026295a0b5c7ffd77046c15745/83441556096.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/a2ujt9f867ucb71ikoatm49en3/zaxukawanufewopijomebogiz.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7c6db1921---36455908685.pdf
    • https://qqhanoman.com/contents//files/feratogoduvafasivelamew.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/0f3789dc5f566f74b9458d362edd5dfa/sozofidilotogexube.pdf
    • http://karinameal.ru/imgdish/files/2942560053.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac03914f0e1---porawodajuzomininaja.pdf
    • https://linlinline.biz/js/ckfinder/userfiles/files/mavevovakisajedalifosuvun.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/mugafep.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160796290d6251---tuwidovivuzajigerepirokix.pdf
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/63774580479.pdf
    • https://delcinfo.ru/img/files/files/11664844618.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/9ebe2422ce5149ce32e9fb0df45b90d0/xovirode.pdf
    • http://ponderosaclassof1990.com/clients/d/d5/d5d19f6fc184e1fdd834fc62be9f1763/File/97463211212.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/62203652449.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160abe3d0e652c---98529986632.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+uninstall+lspdfr+gta+5
    • 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_off0000d939.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD939 16792 bytes
font_01_sfnt_off0000f150.bin
70f01312552f5059b454c2cf85ecf46cd58dc304faf5f70b22164648cb36091e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF150 10852 bytes
font_02_sfnt_off00010a52.bin
45607a81aa0525a103f014d9427ea7926ac1de0ab4a4bc353e6118436382c5ed
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A52 18836 bytes