Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a19366761f1bc4d…

MALICIOUS

PDF

86.1 KB Created: 2021-06-25 20:43:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1512e28c99f27108325a3de8017f7496 SHA-1: a373f5e5e4a1951f73fba7b7dc99bf833537dd0f SHA-256: 8a19366761f1bc4dbfb02a44573faf8f3a2b8a1ba588d12524df0dc557a9157a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, with multiple URLs pointing to compromised WordPress sites and other disposable hosting. These links likely lead to phishing pages or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bdda315dba4---novitokusasajamigogikafe.pdf
    • http://ankaser.com/userfiles/file/53109012267.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f6fb5f2ef---ridip.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be6a8a319bd---kepenisiwesavujunetaz.pdf
    • http://pileshoppen.dk/userfiles/file/zavew.pdf
    • http://smeclassof1987reunion.com/clients/37165/File/12988288236.pdf
    • https://studiorampinelli.com/file/dejesele.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/9873dfb6d2af0a1cd148a639b559836b/42786084027.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/j6u1ft3ugstntiphafeirhvav6/vizapozivosi.pdf
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/9776e2da6350299266a09754f0d6d289/17057068702.pdf
    • https://alternativecarrepair.com/userfiles/file/72594687414.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/nrnos8neo4h0en70u17289eqih/mafapubenotubunufote.pdf
    • https://aydin-elektrik.com/resimler/files/masotizukape.pdf
    • https://btcauction.vn/hinhanh/file/98743782782.pdf
    • http://kag.fr/userfiles/file/tiponupitojovekodawu.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/hd5sn0m2v5mf352v2fg2efh36h/vikavusu.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/d2bb30103bdd2c2b9f0a7997df81ab58/tijorij.pdf
    • https://bandai-k.com/userfiles/file/67190850008.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160956b22e6792---wutowo.pdf
    • http://syuncyoku.jp/upload/file/22367546817.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/i2bvstfef9jrm5776phqdsjilj/574235881.pdf
    • https://aspirans.com/files/file/pagibew.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=what+can+replace+red+wine+vinegar
    • 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_off0000ea91.bin
d4bfbf29ce8b7b3e8ab5675ba792fae9449869375ade2f51f16a91c839b78a5a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA91 18252 bytes
font_01_sfnt_off00011b13.bin
fefff749c228ce6a846753df7d2ca5350b04863f043110b8dadee44834ec1e29
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B13 10648 bytes
font_02_sfnt_off00013337.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13337 16792 bytes