Malicious PDF — malware analysis report

Static analysis result for SHA-256 f390653cc58885f3…

MALICIOUS

PDF

74.7 KB Created: 2021-09-04 07:21:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3aaf8fd6643477a41f2f3ba9af62de53 SHA-1: 4fd260ac9402f933415d9d75e4e76d853553a5a4 SHA-256: f390653cc58885f3d4cc00672085506a30f17632f060e68b1a335e4f1e817947
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress upload directories, indicating an attempt to host malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/i2khm5prnakh8q6t9u7a1r5s0r/1189635602.pdf In PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/15372298034.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/72770781493.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607064121fa0e---54561826850.pdfIn PDF document text
    • https://rumahbaruku.com/contents//files/xebakagugunowabuvanewu.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/88772134055.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/lobalamowumikibid.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/51479871024.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/7b0c2d08412854d4e2f23e4443a79861/66403036300.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/8216370723.pdfIn PDF document text
    • http://fmafirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49159364236.pdfIn PDF document text
    • https://cdmsig.com/ckfinder/userfiles/files/topisiwiwuwavonufobiduj.pdfIn PDF document text
    • https://micsys.in/userfiles/file/xifigijeboxotixalu.pdfIn PDF document text
    • https://mgs-on-track.com/uploads/misc/files/mubopupidu.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/gutopedetufemolud.pdfIn PDF document text
    • https://xn--arbeitskndigungsrecht-best-5zc.de/userfiles/file/4246531979.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/9b0444ee42d19b92aa5a3fb6ad10dec8/44189372725.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/e3bb4defd711847720cfa93acf52b507/44913200518.pdfIn PDF document text
    • http://tfforming.ru/d/files/4270308355.pdfIn PDF document text
    • https://digireg.ru/upload/62930168999.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/fokozitesukimimalini.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/lazupojize.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610c9186480d5---50853087562.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c87b998bb---63397859973.pdfIn PDF document text
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/0800aa3a412e33deb151d8de3fc09287/savinewopefodavovasatu.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/f95c8cebb4dcaa8e3c5e703c4f2ecfd8/xuwokog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=heidenhain+itnc+530+service+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bfeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFEB 16776 bytes
SHA-256: 47d95a581e0659a333d72a9147238610a2f1c4d0a83e205eebcff99bb8643fbc
font_01_sfnt_off0000eb37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB37 11100 bytes
SHA-256: 3aec3388efc41858cc5b6b1d41f7e8d274a00364c28e23fd83208b48cd56011a
font_02_sfnt_off000104f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1