Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a40f2a23a086744…

MALICIOUS

PDF

69.8 KB Created: 2021-09-25 12:10:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ca95778920911cbb9f97202499da757 SHA-1: c9ee8d9512cb9f84c57b4ad2000073bdba2a8d2a SHA-256: 4a40f2a23a086744067b0b167774dbe4ed843a9859adbdd4708f7ec680bff875
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised websites hosting other malicious PDFs. The presence of these links suggests an attempt to lure users to download further malicious content, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware delivery campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6de3a1208---fegujodafabekorizelox.pdf
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/f03ee1cf6921b7d9579df51e375d1283/vuzesalojupa.pdf
    • http://hawaiianhunareiki.it/file/xubutaku.pdf
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/lixirosajeko.pdf
    • http://foto-recepty.sk/images/fotky/65554442453.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16135afa531c51---71032338120.pdf
    • http://shahnawazonline.com/uploads/files/29050281763.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161429941293b5---42846073809.pdf
    • http://imosa.asia/uploads/files/202109091803084285.pdf
    • https://clubkdo.fr/img/pics/files/3063373802.pdf
    • http://lnhaihui.com/userfiles/file/20210916075144_1220458274.pdf
    • http://minuspk.ru/minuspk.ru/userfiles/file/93203816276.pdf
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/03d9c60660227f0a479a4d93f5aa13d0/kejot.pdf
    • http://danguykhoidoanhnghiephp.vn/Upload/files/56233103290.pdf
    • https://callmarkinvestments.com/callmark/files/52880157947.pdf
    • http://amadpich.com/userfiles/file/nokugagedetiguvaluduwa.pdf
    • http://studiotipaldo.com/userfiles/files/sirovewomewevuxuvuge.pdf
    • http://imosa.asia/uploads/files/202109021205172450.pdf
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/a9ebd557ca3e8527a789bafa47ec6456/23454055069.pdf
    • http://xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/85376424323.pdf
    • http://www.blueoak.fr/image/file/menivezapavurexepi.pdf
    • https://2b3la571ga-70p.com/contents/files/mafuzapibuwe.pdf
    • http://siciny.pl/userfiles/file/xazetax.pdf
    • http://fujiya-burbank.com/uploads/files/sifolawisor.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=download+truecaller+premium+gold+mod+apk
    • 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_off0000b11f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB11F 16792 bytes
font_01_sfnt_off0000c936.bin
9fdcf14d875edd52a76f7b2096e3c4e2143f00c8324319f78ae98804c4260967
pdf-font-stream PDF embedded font (sfnt) at offset 0xC936 10968 bytes
font_02_sfnt_off0000e270.bin
237512b02b5fec8cf03bb2dcee2917abaf632bdebffa071197734d07264636c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE270 15544 bytes