Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a81c364095774b9…

MALICIOUS

PDF

75.5 KB Created: 2021-06-25 17:14:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 486f602db07bd1881f81fe78c2869f4c SHA-1: 958c10a8155e9cff37e48b4c7ef22b90921b0c32 SHA-256: 0a81c364095774b90a289d74d81f24f0a844172ad1cb09e52a4ca2fe1d240799
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file contains numerous links pointing to compromised WordPress upload storage and other disposable hosting, indicating a link farm designed to mislead users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct textual clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d7480ed17---tutopepadufezanizogeke.pdf In PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/af514b0b7bc34b5eba3793b7af1e67ca/32889954253.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad5d81e7d5---8423188858.pdfIn PDF document text
    • http://maxidmum.com/images/upload/fck/file/41978785021.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/rbmn31o209khe9sapdqjovdamc/vutuzizosajavo.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/80871189030.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a210bba435a---fedeleviruf.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a340f5d2d18---webasalov.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0325e73c9a---80129410862.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a9f94b8502---64887279903.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/5d757d5edfa680eebace00a0dc934720/tifenetuditirenewew.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/rn34g1k606ujjobs4r39o253b3/tiwefulojejudewikulevere.pdfIn PDF document text
    • http://www.serenissimaservizi.com//files/gunepofuzizesagixoradodu.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16084eb655d01b---15485561977.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba62be1ab5e---65223201902.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6467443f7a---sazukavunusoz.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210609140646.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16081e9d18f6df---zazugifemo.pdfIn PDF document text
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kowuva.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/160abfbe68e390---sezukopezurebenebadusamux.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b095598cacb---vufopiz.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/xibuxegajajibelizebe.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/moxubetisorajikaruniru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=chemistry+lab+manual+for+bsc+1st+yearPDF 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_off0000c22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22B 16564 bytes
SHA-256: 1bc865c623ce1815c5af012b0396c94edf3457cc66e6da53b782188413eb0189
font_01_sfnt_off0000ed37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED37 11040 bytes
SHA-256: 571541e78e1344930578411d807d65129836743580634c7c661d7817d0ff4c3a
font_02_sfnt_off000106d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1