Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab1c7a90765604d2…

MALICIOUS

PDF

88.7 KB Created: 2021-09-06 07:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b26e89233f72c40fbb12d5eac87bc19b SHA-1: 898d21ce5f414130872d4650a1565b47ad8589ce SHA-256: ab1c7a90765604d23e9e47afbb5c727873463f4e3047fe9a0e8a74d07574ea20
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous embedded URLs that point to compromised CMS upload directories. These links likely lead to further malicious content or phishing pages, aiming to deceive users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1612b916e5cec7---neruzatasubebevidin.pdf
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160734dc9c9cec---10853147888.pdf
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa75274b60---zadizavulobune.pdf
    • http://cissi.it/userfiles/files/1523145677.pdf
    • https://combrooncom.com/contents//files/tupolizatereju.pdf
    • https://kaptenhoki.com/contents/files/36030146702.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/numaliwelupeluroz.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/b442da63941c01939b5be6a9033bc7ae/kapomipevopobiponakakedaf.pdf
    • http://xn--12cbg9dihj7egda2g6a7dceb1d2cp4nvgf4f.com/datas/files/xibibobijekekev.pdf
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/v6p91u8ahljhdp2geguvd6fl7o/53767573175.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5db8217c20---rakefubuwazapudobiju.pdf
    • https://economiadecomunion.com/ckfinder/userfiles/files/pixenukunomew.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7b67deb07---4989056756.pdf
    • http://ambulatorioveterinariocamali.com/userfiles/files/xabuwa.pdf
    • https://fleuriste79.fr/ckfinder/userfiles/files/wadusu.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/f7badf1fea357e0cd83a84b32507c784/60896153819.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/c0c6915aedc02978510c4b6673bd9532/soxokawewafe.pdf
    • https://art-eria.pl/mandarynka/pliki/files/20400591024.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160fd08b8e0290---siban.pdf
    • https://almuhja.com/ckfinder/userfiles/files/zamugoxoxemupugume.pdf
    • http://honda-vo.com/upload/file/16406107390.pdf
    • http://ventilatoryzlin.cz/images/file/tadisivuxifixi.pdf
    • https://angelsstaff.com/uploads/file/bedovanukorefuwik.pdf
    • https://afmiletisim.com/resimler/files/gilojakusowedurafibote.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=present+simple+wh+questions+worksheets+pdf
    • 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_off0000f721.bin
479555d3781d162c55832cf532e68fb76978ddab2ea75350e7c0cec2245b4eb4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF721 17244 bytes
font_01_sfnt_off000123d5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123D5 16792 bytes
font_02_sfnt_off00013bec.bin
2af12286770c51055abe13511210c321c3429b4040dce7fb117e190a33ff9ac5
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BEC 11028 bytes